Thanks to the following for commenting on the drafts IEE, HSE, ESD, Intersolar, NAPS Systems, NHBC, Dulas, CREST, DTI Engineering Inspectorate, EST, Solarcentury. Special thanks to Martin Cotterell
The work described in this report was carried out under contract as part of the DTI Sustainable Energy
Programmes. The views and judgements expressed in this report are those of the contractor and do not nec-
essarily reflect those of the DTI. This guide was originally prepared by BRE and others on behalf of the DTI.
Every effort has been made to ensure that the information given herein is accurate but no legal responsibili-
ty can be accepted by the DTI, BRE and their collaborators, for any errors, omissions or misleading statements.
2.1 Design part 1 – d.c. system
Building integrated products/modules
d.c. system - minimum voltage and current ratings
d.c. cables – general
.1 Cable sizing
Cable type and installation method
2.1.12 d.c. switch
2.2 Design part 2 – earthing and lightning protection
2.4 Design part 4 – design approval
2.4.1 DNO approval
INSTALLATION/SITEWORK
SYSTEM INSPECTION, TESTING & COMMISSIONING REQUIREMENTS, DOCUMENTATION & LABELLING
The scope of this document is to supply system installers with information to ensure that a mains-connected PV system meets current UK standards and best practice recommendations. It is primarily aimed at small-scale installations (less than 16A per phase, as per the scope of ER G83/1).
The scope has been extended in this 2nd edition to provide some guidance on larger systems and off-grid battery installations.
Mechanical design of the PV array is not within the scope of this document. BRE digest 489 ‘Wind loads on roof-based Photovoltaic systems’, and BRE Digest 495 ‘Mechanical Installation of roof-mounted Photovoltaic systems’, give guidance in this area.
Any PV system must comply with Health and Safety Requirements, BS 7671, and other relevant standards and Codes of Practice. Much of the content of this guide
is drawn from such requirements. While many UK standards apply in general
terms, at the time of writing there is still relatively little which specifically relates to
a PV installation. However, there are two documents which specifically relate to the installation of these systems that are of particular relevance:
● Engineering Recommendation G83/1 (2003) – Recommendations for the connection of small scale embedded generators (up to 16A per phase) in parallel with public low voltage distribution networks
● IEE Guidance Note 7 to BS 7671 - Special Locations, Section 12 Solar Photovoltaic (PV) Power Supply Systems
From the outset, the designer and installer of a PV system must consider the potential hazards carefully, and systematically devise methods to minimise the risks. This will include both mitigating potential hazards present during and after the installation phase.
The long-term safety of the system can be achieved only by ensuring that the system and components are correctly designed and specified from the outset, followed by correct installation, operation and maintenance of the system. Consideration of operation under both normal and fault conditions is essential in the design stage to ensure the required level of safety. This aspect is covered in the DESIGN section of this guide.
It is then important to ensure that the long-term safety of the system is not compromised by a poor installation or subsequent poor maintenance. Much
of this comes down to the quality of the installation and system inspection and
testing regime. This is covered in the INSTALLATION section of this guide.
Similarly, much can be done during the planning and design stage to ensure that the installation is safe for the installers. In some circumstances the application of the CDM regulations will be required. (Projects that employ fewer than five people on site, and that last less than 30 days, or involve fewer than 500 person-days of work are exempt). All key safety issues affecting the design and installation process are discussed in the guide. The main safety issues are:
● The supply from PV modules cannot be switched off, so special precautions should be made to ensure that live parts are either not accessible or cannot be touched during installation, use and maintenance.
● PV modules are current-limiting devices, which require a non-standard approach when designing fault protection systems, as fuses are not likely to blow under short-circuit conditions.
● PV systems include d.c. wiring, with which few electrical installers are familiar.
● The installation of PV systems presents a unique combination of hazards – due to risk of electric shock, falling and simultaneous manual handling difficulty. All of these hazards are encountered as a matter of course on a building site, but rarely all at once. While roofers may be accustomed to minimising risks of falling or injury due to manual handling problems, they may not be used to dealing with the risk of electric shock. Similarly, electricians would be familiar with electric shock hazards but not with handling large objects at heights.
A mains-connected PV installation generates electricity synchronised with the
electricity supply. Installers are obliged to liase with the relevant Distribution Network Operator (DNO) in the following manner:
● Single installation covered by G83/1 – notification at or before day of commissioning followed by G83/1 paperwork (G83/1 appendix 3) within 30 days.
● Multiple installation covered by G83/1 – application to proceed (G83/1 appendix 2). On commissioning – notification and appendix 3 as above.
● Larger installations under G59/1 – Written approval from DNO to be gained prior to works. Commissioning in conjunction with DNO engineer, or as required by DNO.
1.5 Note on Layout This guide is split into two main parts, the first detailing issues that need to be addressed during the design phase of a project, and the second covering installation and sitework. It is important to note, however, that many ‘design’ issues covered in the first section may have a significant impact on the practical installation process covered in the second.
Throughout the guide the following format has been adopted to show the levels of authority for each guideline:
Bold text in blue against a shaded box with two ticks indicates mandatory and/or broadly recognised requirements (‘must’).
Text in blue with one tick indicates recommended practice (‘should’).
Text marked as notes and in italics indicates explanatory material.
00123 kW
0123 CO2

PV connected
- Single inverter
Single PV string
off position only
- Two PV strings for each inverter
Feed to 3 pole MCB in
(split across
via G59/1
to 3 supply)
phase MCB in main distribution unit
PV cell basic PV device which can generate electricity when exposed to light such as solar radiation
PV module smallest completely environmentally protected assembly of interconnected PV cells
PV string circuit in which PV modules are connected in series, in order for a PV array to generate the required output voltage
PV array mechanically and electrically integrated assembly of PV modules, and other necessary components, to form a d.c. power supply unit
PV array junction box enclosure where all PV strings of any PV array are electrically connected and where protection devices can be located if necessary
PV string cable cable connecting PV modules to form a PV string
PV string fuse a fuse for an individual PV string
PV array cable output cable of a PV array
PV d.c. main cable cable connecting the PV generator junction box to the d.c. terminals of the PV inverter
PV inverter device which converts d.c. voltage and d.c. current into a.c. voltage and a.c. current
PV supply cable cable connecting the a.c. terminals of the PV inverter to a distribution circuit of the electrical installation
PV a.c. module Integrated module/inverter assembly where the electrical interface terminals are a.c. only. No access is provided to the d.c. side
PV installation erected equipment of a PV power supply system
PV Standard test conditions (stc) test conditions specified for PV cells and modules
PV Kilowatts peak (kWp ) units for defining the rating of a PV module where = kW generated at stc
PV self-cleaning The cleaning effect on inclined PV systems from rain and wind etc
PV Charge Controller A device that provides the interface between the PV array and the battery
PV MPP Tracker Maximum Power Point Tracker – the d.c. input stage of an inverter designed to maximise the input from the array
V oc(stc) , Open-circuit voltage voltage under standard test conditions across an unloaded (open) PV module, PV string, PV array, PV generator, or on the d.c. side of the PV inverter
I sc(stc) , Short-circuit current short-circuit current of a PV module, PV string, PV array or PV generator under standard test conditions
d.c. side part of a PV installation from a PV cell to the d.c. terminals of the PV inverter
a.c. side part of a PV installation from the a.c. terminals of the PV inverter to the point of connection of the PV supply cable to the electrical installation
Isolator/ Disconnector A mechanical switching device which, in the open position, complies with the requirements specified for isolation. An isolator is otherwise known as a disconnector. A disconnector is otherwise known as an isolator.
Equipotential Zone where exposed-conductive parts and extraneous-conductive parts are maintained at substantially the same voltage potential
PME – Protective Multiple Earthing where the supply neutral and earth are combined into a single conductor
Distribution Network Operator (DNO) The organisation that owns or operates a Distribution Network and is responsible for confirming requirements for the connection of generating units to that Network.
Electricity Network An electrical system supplied by one or more sources of voltage and comprising all the conductors and other electrical and associated equipment used to conduct electricity for the purposes of conveying energy to one or more Customer’s installations, street electrical fixtures, or other Networks.
Islanding Any situation where a section of electricity Network, containing generation, becomes physically disconnected from the DNOs distribution Network or User’s distribution Network; and one or more generators maintains a supply of electrical energy to that isolated Network.
ROCs Renewable Obligation Certificates equivalent to 1MWh of PV generation
2.1.1.1 Standard Modules
Modules must comply with the international standards: IEC 61215 in the case of crystalline types, or IEC 61646 in the case of thin film types. Modules must also carry a CE mark.
✓ The use of Class II modules is generally recommended, and strongly recommended for array open-circuit voltages of greater than 120 V.
These products should comply with IEC module requirements as above. If no
specific ‘IEC Certificate’ is available (eg for a one-off, bespoke product) a statement and evidence from the manufacturer is required to prove general compliance. In addition, for ‘integrated products’ where the PV forms part of the building envelope (eg PV roof tiles), proof of compliance with relevant Building Regulations may be required by the local Building Control Inspector, eg compliance with:
● Fire resistance standards
● Relevant wind uplift and weatherproofing standards (eg BS 6399, BS 5534, BRE Digest 489).
2.1.2 d.c. System – minimum voltage and current ratings
All d.c. component ratings (cables, isolators/disconnectors, switches, connectors, etc) of the system must be derived from the maximum voltage and current of the PV array. This must take into account system voltage/currents of the series/parallel
connected modules making up the array. It must also take into account the maximum output of the individual modules:
Mono- and multi-crystalline silicon modules :
All d.c. components must be rated, as a minimum, at:
Voltage: V oc(stc) , I sc(stc) I x 1.15 Current: I sc(stc) x 1.25
Note: When considering the voltage and current requirements of the d.c. system, the maximum values that could occur need to be assessed. The maximum values originate from two PV module ratings – the open-circuit voltage (Voc) and the short-circuit current (Isc) which are obtained from the module manufacturer. The values of Voc and Isc provided by the module manufacturer are those at standard test conditions (stc) – irradiance of 1000 W/m 2 , air mass 1.5 and cell temperature of 25 ° C. Operation of a module outside of standard test conditions can considerably affect the values of Voc(stc), Isc(stc).
In the field, irradiance and particularly temperature can vary considerably from stc values. The above multiplication factors allow for the maximum values that may be experienced under UK conditions.
All other module types All d.c. components must be rated, as a minimum, from:
a. Specific calculations of worst case Voc and Isc, calculated from manufacturer’s data for a temperature range of -15°C to 80°C and irradiance up to 1250 W/m 2 b. A calculation of any increase in Voc or Isc over the initial period of operation. This increase is to be applied in addition to that calculated above.
In addition, some modules have an electrical output that is considerably higher during the first weeks of operation. This increase is on top of that produced by temperature/irradiance variation. Typically, operation during this period will take Voc, Isc (and nominal power output) well above any value calculated using a standard multiplication factor. To avoid oversizing for this eventuality the array could be left disconnected for that initial period.
Refer to the manufacturer for this information.
2.1.3 PV Array Design Installations within the UK, using currently available G83/1 type approved inverters, typically operate with array voltages in the range of 120 to 500Vd.c However, it is to be noted that in some circumstances an array design can be implemented where the array is split into sub-arrays with an open-circuit voltage of less than 120 V.
Double insulation (insulation comprising both basic & supplementary insulation, International Electrotechnical Vocabulary IEV 195-06-08), appropriate barriers and separation of parts must be applied to all systems with an open-circuit voltage of >120 Vd.c
Class II insulation on the d.c. part of the PV system, even if less than 120 Vd.c., is strongly recommended.
Note: Double insulation of the d.c. circuit (d.c. wiring, connectors etc) greatly minimises the risk of creating accidental shock current paths (eg via damaged cable coming in contact with PV frame) and the risk of fire. Having a PV junction box with negative and positive parts well separated and protected by barriers, or better still by utilising separate enclosures, significantly reduces the potential shock risk to the installer.
Note: Though commonly used for the main d.c. cable (e.g. for long d.c. cable runs in exposed locations such as on flat roofs, or where cable is buried), sheathed and armoured cable with two or more singly insulated cores does not constitute double-insulated cable, though in this application it is acceptable as it affords a good degree of fault risk reduction (see 2.1.4.2c).
2.1.4 d.c. Cables – General
2.1.4.1 Cable sizing
Cables must be rated, as a minimum, to the voltage and current ratings derived using the multiplication factors in 2.1.2.
Standard de-rating factors must also be applied (BS 7671).
✓ Cables should be sized such that overall voltage drop at stc between the array and the inverter is <3%.
The cables used for wiring the d.c. section of a grid-connected PV system need to be selected to ensure that they can withstand the environmental, voltage and current conditions at which they may be expected to operate. This will include heating effects of both current and solar gain.
Note: Purpose designed “PV cables” are readily available. These are simple to use, comply with the requirements as above and allow simple and safe connection via purpose made PV plug and socket connectors. It is expected most installations would use these cables.
Cables routed behind a PV array must be rated for a minimum temperature of 80˚C.
Cables must be selected so as to minimise the risk of earth faults and short-circuits. This can be achieved by reinforcing the protection of the wiring either through:
a. Single conductor cable – both insulated and sheathed (eg “PV cable”,
HO7RNF cables)
b. Single conductor cable in suitable conduit/trunking (typically non
conducting, however earthed metal trunking may be required where additional mechanical protection is required.) Alternatively, single core SWA may be a suitable mechanically robust solution.
c. Multi core Steel Wire Armoured SWA (only suitable for main d.c. cable
and typically utilised where an underground or exposed run is needed)
External cables should be UV stable, water resistant, and it is recommended that they be flexible (multi-stranded) to allow for thermal/wind movement of arrays/modules.
Note: To minimise the risk of faults, cable runs should be kept as short as practicable. Where long cable runs are required, it is good practice to label along the d.c. cables as follows: “Danger solar PV array cable – high voltage d.c. - live during daylight”. This is to inform personnel involved in maintenance or alterations to a building at a later date. See also section 2.1.12
Note: Where modules are supplied with pre-fitted single insulated tails, containment should be installed - as described in (b) above.
Note: New cable identification colours have been implemented under the current version of BS 7671 (see 2.3.1). The new identification colours for an unearthed d.c. circuit (typical PV circuits) are as follows:
Positive cable - Brown Negative cable - Grey
Note: BS 7671 requires that every core of a cable shall be identifiable by colour and/ or lettering/numbering at its terminations and preferably throughout its length. However, in the special case where there is no possibility of confusion, eg where cables are pre-fitted with purpose made polarised plug and socket connectors (+,-), additional cable colour/alphanumeric identification may be omitted. Binding and sleeves for identification purposes shall comply with BS 3858 as appropriate.
A string is a circuit in which PV modules are connected in series, in order for
a PV array to generate the required output voltage.
Main d.c.
For a system of N parallel connected strings, with each formed of M series connected modules, string cables are to be rated as follows:
a. Array with no string fuses (of three or fewer strings only) Voltage: V oc(stc) x M x 1.15 Current: I sc(stc) x (N-1) x 1.25
b. Array with string fuses Voltage: V oc(stc) x M x 1.15 Current: I sc(stc) x 1.25
The sizing process for string cables in arrays with three or fewer series connected strings is valid for the majority of silicon-crystalline (conventional) modules. However, when applying this rule, a system designer must verify with the manufacturer that the individual modules are capable of withstanding a reverse current of 2 x 1.15 x Isc. See section 2.1.10 for further information.
Note: PV module string circuits cannot rely on conventional fuse protection for automatic disconnection of supply under fault conditions. This is because the short-circuit current is little more than the operating current – a fuse would simply not operate.
A photovoltaic cell acts as a current source, hence PV modules are current- limiting devices – even under short-circuit conditions, the output current of a module will not rise above a certain level (Isc). Operating a module in short- circuit is in general of little consequence, indeed many charge controllers in battery charging systems routinely short-circuit an array output. For small systems, the simplest approach is to ensure that the string cables are suitably rated such that they may safely carry the maximum possible fault current. This method relies on oversizing the string cables such that the fault current can be safely accommodated. Such a method does not clear the fault but simply prevents a fire risk from overloaded cables.
String fuses are required for systems of four or more strings – see string fuse section for more information. For a system with string fuses, cables may be sized by applying the standard voltage and current multiplication factors.
For a system of N parallel connected strings, with each formed of M series connected modules, d.c. main cables must be rated as a minimum at:
Voltage: V oc(stc) x M x 1.15 Current: I sc(stc) x N x 1.25
PV specific plug and socket connectors are commonly fitted to module cables by the manufacturer. Such connectors provide a secure, durable and effective electrical contact. They also simplify and increase the safety of installation works. They are recommended in particular for any installation being performed by a non-PV specialist – eg a PV array being installed by a roofer. Plug and socket “Y” connectors can also be used to replace a junction box. It is good practice to keep “Y” connectors in accessible locations and where possible note their location on layout drawings, to ease troubleshooting in future.
Connectors must be d.c. rated.
Connectors must have the same or greater voltage and current ratings
as the string/d.c. main cable to which they are fitted.
A sign, ‘Do not disconnect d.c. plugs and sockets under load – turn off
a.c. supply first’ must be fixed next to connectors, except those that are
inaccessible to anyone except trained personnel in the course of PV maintenance or fault finding.
Connectors must not be used as the means for d.c. electrical switching (see 2.1.12) as d.c. arcs can cause permanent damage to some connectors.
Note: Plugs used in this application can be damaged by arc currents if disconnected under load. While connectors are sometimes suggested as an alternative to specifying a d.c.-rated switch, such use is not permitted.
✓ Connectors should be touch safe (ie to a standard of ingress protection not less than IP 21), Class II and shrouded, and be of a design totally dissimilar in appearance to any connectors used for the a.c. system.
In general cable junctions will be either by an approved plug and socket connector or contained within a d.c. Junction Box (see below). However in certain limited circumstances it may be necessary for an in-line cable junction to be made (eg soldered extension to a module flying lead) although this should be avoided if at all possible.
Note: Great care needs to be applied in the design and installation of in-line junctions. Where unavoidable, such junctions need to maintain the ‘double insulated’ nature of the cables as described in section 2.1.4 (eg by the use of two layers of appropriately rated adhesive lined heat shrink sleeving), and be provided with appropriate strain relief. Such junctions would typically be done off-site, prior to works, using fittings and tools appropriate to the cable to be jointed.
If there is more than one string, the d.c. junction box is normally the point at which they are connected together in parallel. Junctions need to be made using high quality connectors, typically screw terminals. The box may also contain string fuses and test points.
The d.c. junction box must be labelled as ‘PV array d.c. junction box’, and also labelled with ‘Danger, contains live parts during daylight’. All labels must be clear, legible, located so as to be easily visible, and durably constructed and affixed to last.
Note: A PV system cannot be turned off – terminals will remain live at all times during daylight hours. It is important to ensure that anyone opening an enclosure is fully aware of this.
A readily accessible disconnection device shall be provided to isolate
individual strings. Isolation shall be provided in both positive and negative string cables.
Note: String isolation shall be achieved by any suitable means such as appropriately located plug and socket connectors or removable string fuses. Any such isolation should not be carried out with the system under load.
The short-circuit protection afforded by the cable installation throughout the rest of the d.c. circuit needs to be maintained in the construction and makeup of the d.c. junction box. (See IEC 60536 and IEC 61140).
It is recommended that short-circuit protection shall be achieved by:
● Fabrication of the enclosure from non-conductive material
● Positive and negative busbars adequately separated and segregated within the enclosure and/or by a suitably sized insulating plate, or separate positive and negative junction boxes.
● Cable and terminal layout such that short-circuits during installation and subsequent maintenance are extremely unlikely.
2.1.10 String Fuses For a system of N parallel connected strings, with each formed of M series connected modules:
String fuses must be provided for all arrays formed of four or more strings. Fuses must be fitted in both positive and negative string cables for all strings.
● The string fuse must be rated for d.c. operation at the fault energies present
● The string fuse must be rated for operation at V oc(stc) x M x 1.15
● The string fuse must have a tripping current which is less than 2 x Isc (stc) and the string cable current carrying capability, whichever is the lower value.
Note: The requirement for omitting string fuses in arrays with three or fewer series connected strings is valid for the majority of silicon-crystalline (conventional) modules. However, when applying this rule, a system designer must verify with the manufacturer that the module is capable of withstanding a reverse current of 2 x 1.15 x Isc.
For some modules, the reverse current rating provided by the manufacturer may permit more than three parallel connected strings to be installed without string fuses. In such cases, the number of strings that may be connected in parallel without the use of fuses is calculated by ensuring:
Ir > I (stc) x (N-1) x 1.25 where Ir is the maximum permitted reverse current quoted by the module manufacturer.
The use of fuses or MCBs (miniature circuit breakers) is permissible provided they meet the above criteria and are rated for use in an inductive circuit and will operate for currents flowing in either direction through the device.
For a system of three or fewer strings with NO string fuses, string cables must have a minimum current rating of: Isc (stc) x (N-1) x 1.25
Note: In a PV array formed from a number of strings, fault conditions can give rise to fault currents flowing though the d.c. system. Two key problems need addressing – overloaded string cables and significant module reverse currents, both of which can present a considerable fire risk.
Fault analysis shows that the maximum fault current flowing in a string cable to be (N -1) x Isc. A system of three or fewer strings cannot generate sufficient fault currents to present hazardous module reverse currents. Hence with three or fewer strings, fuses can be omitted providing that string cables are suitably rated. Such a method does not clear the fault, but simply prevents a fire risk from overloaded cables.
The installation of string fuses can provide protection against fault currents in all other cases. While some fault combinations are less likely than others, in order to provide full protection of all cables and modules – string fuses are required in both the positive and negative legs of the string cabling. (See section 2.1.5).
Note: As in section 2.1.9 it is required that some suitable means of electrical isolation be provided. This will also enable engineers to separate out individual strings for testing and tracing faults. A system fitted with suitable removable string fuses provides an ideal way to accomplish this. Thus, while it may not be necessary to fit string fuses on an array formed from two or three strings, their use may still be beneficial.
2.1.11 Blocking Diodes Blocking diodes are not commonly used in a grid-connect system as their function is better served by the installation of a string fuse. Historically, they were specified
to prevent any reverse current flowing through parallel connected strings, much as a string fuse is intended to do. However:
● the installation of a blocking diode results in a small voltage drop across the diode;
● blocking diodes may fail as a short-circuit and therefore require regular testing. Specification of string fuses can provide sufficient reverse current protection without the problems and power losses associated with a blocking diode.
If specified, a blocking diode must have as a minimum a reverse voltage rating of 2 x Voc x number of modules in the string (stc).
2.1.12 d.c. Switch The d.c. switch provides a means of manually electrically isolating the entire PV array. Such electrical isolation is required during system installation and subsequent system maintenance or repair work. It should be located adjacent to, or integrated into the inverter.
An additional d.c. switch may be specified for systems with long d.c. cable runs (typically at the point of cable entry into the building) – so as to provide a means of isolating the cable for safety reasons or maintenance works.
● The d.c. switch must be double pole – to effectively electrically isolate both PV array positive and PV array negative.
● The d.c. switch must be rated for d.c. operation.
Note: Switching a.c. is less demanding than switching d.c. – with an a.c. supply, the voltage passes through 0 V many times a second. A switch must be rated to break d.c.; an equivalent a.c.-rated switch is not acceptable or safe.
● The d.c. switch should be load-break rated (the use of non load-break switches is not recommended).
● The d.c. switch must be rated for the system voltage and current maxima as calculated in section 2.1.2.
● The d.c. switch (or switches) must be labelled as ‘PV array d.c. isolator’, with the ON and OFF positions clearly marked. Switch enclosures must also be labelled with ‘Danger - contains live parts during daylight’. All labels must be clear, easily visible, constructed and affixed to last and remain legible for as long as the enclosure.
2.2 Design Part 2 – Earthing and Lightning Protection Connection of parts of a PV system to earth affects:
● The electric shock risk to people in the vicinity of the installation
● The risk of fire under fault conditions
● Transmission of lightning induced surges
● Electromagnetic interference
Two types of connection to earth need consideration:
a) Earthing of exposed conductive parts
b) System earths – where an array output cable is connected to earth
The earthing arrangements recommended in this guide are based upon those given in BS 7430, BS 6651 and BS 7671.
2.2.1 Earthing of exposed conductive parts (array frame) The majority of installations will utilise class II modules, class II d.c. cables & connectors and be connected to the mains via an inverter with an isolation transformer. This approach is recommended and permits the array frame to be left floating.
Notes to terms used in diagram:
a) Isolating transformer: An isolating transformer is one in which the input and output windings are electrically separated by double or reinforced insulation (see BS 3535). While the hazards presented by an array frame reaching the system d.c. potential may be significant, the potential fault/shock current is typically much less than that from a mains fault. Hence it is the electrical separation of the mains from the d.c. using an isolating transformer that is the key determining factor when assessing the requirement for array frame earthing.
Array Frame Earthing Decision Tree:
• Class II modules?
• Class II Cables, connectors/ions & Junction Boxes
• Isolation Transformer in Inverter?

• In Equipotential Zone?
(Note: freestanding ground mounted, or building roof
mounted arrays (away from building metalwork) will
normally not be within the equipotential zone. However, a
solar thermal system, or other building linked metalwork,
installed within reach may extend the equipotential zone
Install & bond to earth spike
(Note: do not take PME out of
equipotential Zone)

Bond direct to Consumer
(Note: If an earth spike is already installed for Lightning Protection, bond to this braid)
b) ‘Equipotential Zone’ is defined as a zone in which exposed-conductive parts
and extraneous-conductive parts are maintained at substantially the same potential by bonding, such that, under fault conditions, the differences in potential between simultaneously accessible exposed and extraneous-conductive parts will not cause electric shock. ‘Extraneous-conductive parts’ are conductive parts liable to introduce a potential, generally earth potential, and not forming part of the electrical installation, such as a water pipe, outside tap, a metal downpipe – anything conductive that is connected to ‘Earth’ but not electrically part of the system.
c) PME – Protective Multiple Earthing – an earthing arrangement whereby the
supply neutral and earth are combined into a single conductor. Where the incoming supply is PME (the majority of domestic supply arrangements), the PME earth cannot be taken outside the equipotential zone. This is to prevent the potential shock hazard should the supply neutral ever be lost.
✓ The bonding to earth of any of the current carrying d.c. conductors is not recommended. However as in the note below, earthing of one of the live conductors of the d.c. side is permitted, if there is at least simple separation between the a.c. side and the d.c. side, including in the inverter.
Note: In some countries it has been the practice to bond one part of the d.c. current conductors to earth (eg earth connection at midpoint of PV string or earthed d.c. negative), or for performance reasons on certain types of modules to earth the d.c. positive. Due to the increased possible earth fault paths, and possible problems with commonly available European inverter types and internal earth fault detection circuitry, such practice should only be made when unavoidable (any connections with earth on the d.c. side should be electrically connected so as to avoid corrosion).
The inverter must be treated as standard electrical apparatus and earthed as per BS 7671 if Class 1.
Lightning can cause damage either from a direct strike or from surges due to a nearby strike. Induced surges are the more likely cause of lightning damage in the majority of installations, especially in rural areas where electricity supplies are usually by long overhead lines. Surges may be induced on both the PV array conductors or the a.c. cables leading to the building.
2.2.4.1 Lightning Protection Systems
✓ Where there is a perceived increase in risk of direct strike as a consequence of the installation of the PV system, specialists in lightning protection should be consulted with a view to installing a separate lightning protection system in accordance with BS 6651.
Note: It is generally accepted that the installation of a typical roof-mounted PV system presents a very small increased risk of a direct lightning strike. However, this may not necessarily be the case where the PV system is particularly large, where the PV system is installed on the top of a tall building, where the PV system becomes the tallest structure in the vicinity, or where the PV system is installed in an open area such as a field.
Note: In some cases it may be possible to forgo bonding to the LPS if the array frame is sufficiently far away from it. A system for determining whether it is necessary can be found in BS 6651 – ‘Code of Practice for Protection of Structures against Lightning’. Alternatively, consult the installers of the LPS.
Where an LPS is fitted, PV system components should be mounted away from lightning rods and down leads ( see BS 6651). For example, an inverter should not be mounted on an inside wall that has a down lead running just the other side of the brickwork on the outside of the building.
2.2.4.2 Surge Protection measures
Note: These measures will act to both shield the cables from inductive surges and, by increasing inductance, attenuate surge transmission. Be aware of the need to allow any water or condensation that may accumulate in the conduit or trunking to escape through properly designed and installed vents.
Most grid connect inverters have some form of in-built surge suppression, however discrete devices may also be specified.
Note: To protect the a.c. system, surge suppression devices may be fitted at the main incoming point of a.c. supply (at the consumer’s cut-out).
To protect the d.c. system, surge suppression devices can be fitted at the inverter end of the d.c. cabling and at the array.
To protect specific equipment, surge suppression devices may be fitted as close as is practical to the device.
An inverter supplied from a PV array must preferably be installed in a dedicated circuit in which:
● no current-using equipment is connected, and
● no provision is made for the connection of current-using equipment, and
● no socket-outlets are permitted.
An inverter must not be connected by means of a plug with contacts which may be live when exposed.
Where an electrical installation includes a PV power supply system without at least simple separation between the a.c. side and the d.c. side, an RCD installed to provide fault protection by automatic disconnection of supply must be type B RCD according to BS EN 60898 (IEC 60755, amendment 2).
✓ The a.c. cable connecting the inverter(s) to the consumer unit should be oversized to minimise voltage drop. A 1% drop or less is recommended. However in larger installations this may not be practicable or economic due to the very large size of cable resulting. In this case the designer should minimise voltage drop as far as possible and must remain within voltage drop limits as prescribed by BS 7671.
Note: When generating, the voltage at the inverter terminals is higher than the voltage at the consumer unit. This voltage drop must be kept to a minimum in order to prevent the inverter nuisance tripping on over voltage. Note: New cables colours have been implemented under the current version of BS 7671. These colour changes became mandatory on 1st April 2006. Colour changes and the requirements for labelling in mixed colour installations can be found in BS 7671 and from IEE technical publications.
A manual a.c. switch-disconnector must be provided located in an accessible position within the Customer’s installation as in G83/1 (e.g. adjacent to the consumer unit or main distribution board), which is:
● in accordance with BS 60947-3
● must switch all live and neutral conductors.
● must be securable in the OFF position only. It must be simple to secure using a standard padlock - devices that require a separate removable
adaptor or special key to enable them to be secured are not acceptable.
● must clearly show the ON and OFF positions and be labelled as ‘PV system – main a.c. isolator’.
Note: At the point of installation of any a.c. switch-disconnector, the public supply should be considered the source and the PV installation the load.
If the a.c. switch-disconnector and the inverter(s) are not in the same room
a local isolator should be installed adjacent to the inverter(s). This is to
facilitate maintenance of the a.c. cable run and inverter(s).
Inverters must carry a Type Test certificate to the requirements of Engineering Recommendation G83/1 or comply with all other parts of ER G83/1 unless specifically agreed by an engineer employed by or appointed by the DNO for this purpose, and in writing.
Note: A key safety consideration is that the PV system will disconnect when the distribution system is not energised. This is to prevent the hazardous situation of the photovoltaic system feeding the network or local distribution system during a planned or unscheduled loss of mains. Such an event is termed ‘islanding’ and presents a potential danger to those working on the network/distribution system. Type Tests established through ER G83/1 ensure that an inverter is properly prevented from such islanding operation.
Other considerations addressed by ER G83/1 include the prevention of harmonics, EMC compatibility and d.c. injection.
In order to simplify the earthing requirement, an inverter with an isolating transformer is recommended (see section 2.2.1.(a)). This would protect against the possibility of a.c. exciting the d.c. side, and remove the requirement to earth the array frame, but does not override any need to connect the frame to earth for lightning protection purposes.
✓ It is recommended that Inverters carry a sign ‘Inverter - isolate a.c. and d.c. before carrying out work’.
Note: Short-circuit protection is not required at the inverter output.
If using an RCD for a.c.-side earth fault protection, see section 2.3.1.
✓ Inverter output meter: As a minimum, metering at the inverter output should be installed to display/record energy delivered by the PV system (kWh). In addition it is highly recommended for instantaneous power output (kW) to be displayed. This will not only add to customer satisfaction it should lead to more effective fault detection. A kWh meter approved by OFGEM is recommended as it may facilitate payment on ROCs and other Electricity company scheme payments as they become available.
The meter should be located where the consumer can readily observe it.
Building Export meter: Although not directly part of the PV system, in order to enable payment on exported electricity, a kWh export meter approved by OFGEM with appropriate meter reading may be required. The appropriate Electricity Supplier should be contacted to find out any particular requirements and to arrange for its fitting.
Installers are obliged to liase with the relevant distribution Network Operator (DNO) in the following manner:
Guidance regarding the requirements for planning permissions for PV systems can be obtained in PPS22 ‘Planning Policy Statement 22: Renewable Energy’ (ISBN <DIGITS>, 2004 - available from www.odpm.gov.uk).
The relevant planning authority and building control should be consulted at an early stage to determine any requirements that may apply.
Note: Planning permission will be mainly concerned about the visual impact of the PV system. Typically, for domestic installations, planning permission is not required (can vary where property is affected by restrictions such as a conservation area, etc).
Building Regulations approval may require the product to have passed the wind uplift, water penetration and spread of flame tests (see section 2.1.1.2). These will usually be applicable only where the PV is integrated into the fabric of the building.
2.4.3 Building Regulations – Part P
From 1st January 2005, people undertaking electrical work in homes and gardens in England and Wales must follow new rules in Building Regulations - Part P.
● Ensure the safety of electrical installations
● Ensure records are kept of work done
● Provide electrical safety certificates that verify conformity of work – these may be integrated into property selling requirements
Virtually all domestic PV installations will fall under the scope of Part P. Part P requires the relevant Building Control department to be notified and approve the work. There are two routes to comply with the requirements of Part P:
● Notify the relevant Building Control department before starting the work. Documentation will be required and a site inspection by a Building Control officer may occur. Building Control charges may apply.
● Where a contractor is registered with a Competent Person Scheme (as approved by the office of the deputy prime minister), Building Control can be supplied with relevant documentation after the work is completed. Documentation is self certified under the Competent Person Scheme and a site visit by Building Control is not normally required.
Part P also reinforces the requirement for the provision of an Electrical Installation Certificate (to the requirements of BS 7671) – see section 4.1.
Note: A copy of the ‘Building Notice’ notification form can be found on the Local Authority Building Control website www.labc-services.co.uk.
Note: At the time of writing, there are no ‘defined scope’ competent persons schemes to cover the installation of PV systems. Until a PV defined scope scheme is available, full scope schemes are applicable.
2.5 Battery Systems This section of the guide covers the additional requirements where a battery forms part of a PV installation – whether as part of a true stand-alone (off-grid) system or part of a hybrid (e.g. grid-linked/ batteries) system.
Note: The design and requirements of any of the load circuits within such a system are outside the scope of this document.
2.5.1 PV array charge controller This provides the regulator/dump interface between the PV array and the battery so as to prevent overcharging of the battery. The unit may also provide other functions such as maximum power point tracking, voltage transformation, load control and metering.
(4 parallel PV
(inc string
fuse disconnects)
main fuse disconnect
● The charge controller must be rated for the current and voltage maxima
● The charge controller must be labelled as per the d.c. junction box requirements in section 2.1.9.
● The charge controller must carry a CE Mark.
2.5.2 Battery over current protection
A battery stores significant energy and has the capacity to deliver large fault
currents. Proper fault protection must be provided.
An over current device must be installed in all active (non-earthed) conductors between the battery and the charge controller.
The over current device (either a fuse or circuit-breaker) must:
● have a trip value as specified within the charge controller manual
● be rated for operation at d.c., at 125% of the nominal battery voltage
● have an interrupt rating greater than the potential battery short- circuit current.
The length of cable between the over current device and battery terminal must be as short as practicable.
A means of manual isolation must be provided between the charge
controller and the battery, either combined with the over current device
or as a separate unit. The isolator must be double pole, d.c. rated and
load break, and the length of the cable between it and the battery must
Isolation is to be installed and the system designed so that the PV array
cannot directly feed the loads when the battery has been disconnected.
Combined fault protection and isolation:
● A circuit-breaker provided for battery fault current protection may be
used to provide isolation, if it is rated as an isolation device.
● A fuse assembly provided for fault current protection may be used to provide isolation if it has readily removable fuses
The requirements set out in the main sections of this guide apply:
Note: In some circumstances, a voltage drop greater than that in section 2.1.4.1 may be justified on economic grounds.
All cables must have a current rating above that of the relevant over current device (nearest downstream fuse / circuit breaker). Cable current ratings are to be adjusted using standard correction factors for installation method, temperature, grouping and frequency to BS 7671.
String cables (upstream of the charge controller) must be rated to the trip current of the nearest downstream device plus the rating as calculated in section 2.1.5.
A PV–battery system must be designed such that the string cable/ string fuse
design and specification reflects that fault currents may come either from the array itself, from the battery or from both. Again, cable current ratings are to be
adjusted using standard correction factors for installation method, temperature, grouping and frequency to BS 7671.
Note: Specification & labelling for the PV cables/ junction boxes/ connectors/ etc should be as in the main sections of the guide.
The selection of a battery is generally out of the scope of this document. However, some key considerations to be flagged are:
● is the battery fit for purpose, i.e. appropriately rated for its duties? In the majority of cases a true ‘deep cycle’ battery will be required
● does it have an adequate storage capacity and cycle life?
● is a sealed or vented battery more appropriate for the particular installation?
● will the battery be made up of series cells or parallel banks? While series cells will generally give better performance, practical considerations may influence the design. In general, though, banks with more than four parallel units are to be avoided.
Charge/discharge rates (C) are commonly expressed as an hourly rate derived from the formula: Rate = Capacity (Ah) / Time (h) For example, a C10 charge rate for a 500Ah battery would take place at 50A.
Charge rates between C5 and C20 are often used in systems with vented lead acid batteries, for example.
In an enclosed location, ventilation must be provided to battery installations with an air inlet at low level and an outlet at the highest point in the room or enclosure.
Sufficient ventilation is needed to remove battery gases. It is particularly important in the case of vented lead acid units as hydrogen is given off during charging – and a concentration of more than 4% creates an explosion hazard. Ventilation also prevents excessive heat build up.
BS 6133 ‘Safe operation of lead acid stationary batteries’ gives a procedure for calculating ventilation requirements.
Battery banks must be housed in such a way that (BS 6133):
● access can be restricted to authorised personnel
● adequate containment is assured
● appropriate temperature control can be maintained
Battery terminals are to be guarded so that accidental contact with persons or objects is prevented.
The ideal operating temperature for a lead acid battery is around 25ºC, temperatures significantly above or below this will lead to reduced lifetime and capacity. Indeed, at very low temperatures, discharged batteries may freeze and burst; at high temperatures, thermal runaway can occur in sealed batteries.
Items which could produce sparks (e.g. manual disconnects, relays) should not be positioned within a battery box or directly above one.
Battery gases are corrosive, so cables and other items inside a battery enclosure need to be corrosion resistant. Sensitive electronic devices should not be mounted in, or above, a battery box.
To ensure proper load/charge sharing in a battery bank made up of units connected in parallel, the units need to have the same thermal environment and
In larger battery banks, fusing each parallel unit should be considered.
A typical connection configuration for a small series-parallel battery bank

The following warning signs are to be displayed:
● No Smoking or Naked Flames
● Batteries contain acid – avoid contact with skin or eyes
● Electric shock risk – xxx Vd.c.
All labels should be clear, easily visible and should be constructed and fixed so as to remain legible and in place throughout the design life of the system.
Protective equipment, including appropriate gloves and goggles – together with an eye wash and neutralising agent – should be stored adjacent to the battery installation.
It is common practice for an inverter power to be less than the PV array rating and
safety considerations with respect to sizing an inverter are addressed in section
2.3.3. However, also to be considered is the system performance.
For example, a 1kWp array connected to a 1.5kW inverter may be safe but not energy efficient – with the UK climate, the inverter will be operating for much of the time at less than the 1kWp rating of the array and consequently at a poor point on the inverter efficiency curve depending on the inverter (inverters are typically less efficient at low power levels).
PV array: inverter ratios from 1:1 to 1:0.8 are commonly applied in the UK, though in certain circumstances and depending on the inverter used, ratios
Guidance on inverter : array sizing can be obtained from the inverter manufacturers – typically from system sizing software.
Inverter mpp range - An inverter must be able to safely withstand the maximum array voltage and current as stated in section 2.3.3. However, when chosing the most appropriate inverter, for inverter performance purposes and when considering the matching of an array to the mpp range of an inverter, an assessment can be made as to whether a narrower temperature band (e.g. -10˚c to 70˚c) maybe acceptable and appropriate for that particular site.
Note: These figures are typical for the UK - up to +/-10% difference can be expected depending on position in the country and type of PV cells used etc - it is recommended that a PV simulation is carried out using one of the PV simulation programmes available for an accurate estimation.
Orientation Chart - Showing % of yearly output available for various orientation tilts
Average Production per season

July Global Irr. clear sky
October Global Irr. clear sky
April Global Irr. clear sky
January Global Irr. clear sky
Example average daily isolation curves: Manchester, 300 Inclination, due South. Ref: European Joint Research Centre, <URL> pvgis/pv/ PVGIS©European Communities, 2002-2006
Example average kWh electricity generation bar chart:
Manchester, 30° Inclination, due South, 750kWh/yr Ref:
European Joint Research Centre, <URL> pvgis/pv/ PVGIS©European Communities, 2002-2006
Shading – Shade makes a big impact on the performance of a PV system. Even
a small degree of shading on part of an array can have a very significant impact
on the overall array output. Shade is one element of system performance that can be specifically addressed during system design – by careful selection of array
location and layout and in the electrical design (string design to ensure shade effects only one string).
Module temperature – An increase in module temperature results in a decrease in performance (eg 0.5% per 1°C above stc for a crystalline module). Sufficient ventilation must be provided behind an array for cooling (typically a minimum 25mm vented air gap to the rear). For building integrated systems, this is usually addressed by the provision of a vented air space behind the modules. On a conventional pitched roof, batten cavity ventilation is typically achieved by the use of counterbattens over the roof membrane and by the installation of eaves and ridge ventilation.
Note: It may be possible to omit counterbattens with some integrated PV roofing products / roof construction. This is acceptable where there is test data showing that a specific integrated PV product and associated roof construction provide a similar PV cell temperature performance to a roof with a ventilated counterbatten space.
Inverter ventilation – Inverters dissipate heat and should be provided with
sufficient ventilation. Clearance distances as specified by the manufacturer (e.g to
a heatsink) should also be observed. Failiure to follow this can cause a loss in
system performance as the inverter will de-rate when it reaches it’s maximum operating temperature. This should be highlighted within the O&M manual and perhaps with a label – not to block ventilation – placed next to the inverter.
Standard health and safety practice and conventional electrical installation practice must apply to the installation of a PV system. Issues such as working on roofs or standard domestic a.c. wiring are covered thoroughly in other publications (e.g. see HSE website www.hse.gov.uk) and are not detailed in this guide.
When compiling a method statement and risk assessment for the installation of a PV system, there are a number of PV specific hazards that need to be addressed. These will be in addition to standard considerations such as PPE (Personal Protective Equipment), working at height, manual handling, handling glass and the application of the CDM regulations.
● PV modules produce electricity when exposed to daylight and individual modules cannot be switched off. Hence, unlike most other electrical installation work, the electrical installation of a PV system typically involves working on a live system. See requirements of Regulation 14 of Electricity at Work Regulations 1989.
● As current limiting devices, PV module string circuits cannot rely on fuse protection for automatic disconnection of supply under fault conditions, as the short-circuit current is little more than the operating current. Once established, a fault may remain a hazard, perhaps undetected, for a considerable time.
● Good wiring design and installation practice will serve to protect both the system installers and any persons subsequently coming into contact with the system from an electric shock hazard (operator, owner, cleaner, service engineers, etc).
● Undetected, fault currents can also develop into a fire hazard. Without fuse protection to clear such faults, protection from this fire hazard can be achieved only by both a good d.c. system design and a careful installation.
● PV presents a unique combination of hazard – due to risk of shock, falling, and simultaneous manual handling difficulty. All of these hazards are encountered as a matter of course on a building site, but rarely all at once. While roofers may be accustomed to minimising risks of falling or injury due to manual handling problems, they may not be used to dealing with the risk of electric shock. Similarly, electricians would be familiar with electric shock hazards but will not be used to handling large objects at heights.
All persons working on the live d.c. cabling of a Photovoltaic (PV) system must be experienced/trained in working with such systems and fully acquainted with the voltages present on that system in particular.
Plug and socket connectors simplify and increase the safety of installation works – see section 2.1.7. They are recommended in particular for any installation being performed by a non-PV specialist – eg a PV array being installed by a roofer.
✓ All d.c. wiring should if possible be completed prior to installing a PV array. This will allow effective electrical isolation of the d.c. system (via the d.c. switch-disconnector and PV module cable connectors) while the array is installed; and effective electrical isolation of the PV array while the inverter is installed.
Typically this would require an installation of:
● d.c. switch-disconnector and d.c. junction box
● String/array positive and negative cables – from the d.c. disconnect/junction box to either end of the PV string/array;
● PV array main cables from d.c. switch to inverter.
✓ This should be carried out in such a way that it should never be necessary for an installer to work in any enclosure or situation featuring simultaneously accessible live PV string positive and negative parts.
Note: While the installer will be handling live cables during the subsequent module installation, because the circuit is broken at the d.c. switch-disconnector, there is no possibility of an electric shock current flowing from the partially completed PV string. The maximum electric shock voltage that should ever be encountered is that of one individual PV module.
Where it is not possible to pre-install a d.c. isolator (eg a new-build project where a PV array is installed prior to the plant room being completed), cable ends/ connectors should be put temporarily into an isolation box and suitably labelled (as per d.c. junction box – section 2.1.9).
If it is unavoidable to work in any enclosure or situation featuring
simultaneously accessible live PV string positive and negative parts, this must be performed either by utilising insulating gloves, tools, insulating materials for shrouding purposes and appropriate personal protective equipment (see Regulations 4(4),14 and 15 of Electricity at Work Regulations 1989; HSE HSG 85; and BS EN 60903 and BS EN 60900) or by covering the PV array; or by working at night (with appropriate task lighting). When covering PV panels during installation, the covering must be opaque, cover the whole array and be well secured.
A temporary warning sign and barrier must be posted for any period
while live PV array cables or other d.c. cables are being installed.
Note: Covering a PV array can provide a means to prevent the need for live working. In practice, however, this is often difficult due to the practical problems of keeping the array covered as the installation proceeds and protecting the covering from the effects of the weather.
It is important to note that, despite all the above precautions, an installer or service engineer may still encounter an electric shock hazard:
Always test for the presence of voltage of parts before touching any part of the system. Where a residual electric shock hazard is encountered, live working practices must be adopted (see above).
An electric shock may be experienced from a capacitive discharge – a charge may build up in the PV system due to its distributed capacitance to ground. Such effects are more prevalent in certain types of modules and systems, namely amorphous (thin film) modules with metal frames or steel backing. In such circumstances, appropriate and safe live working practices must be adopted.
An example of where such hazards may be encountered is the case where an installer is seated on earthed metal roof wiring a large PV array. In such circumstances the installer must touch the PV cabling and can get an electric shock to earth. The electric shock voltage will increase with the number of series connected modules. The use of insulated tools and gloves, together with insulating matting to stand or sit on, can mitigate this hazard.
Inspection and testing of the completed system to the requirements of BS 7671 must be carried out and documented. Provision of this documentation is a requirement of Part P of the Building Regulations
PV array/string performance tests are recommended to verify performance as a check for faulty modules. These will entail additional tests over and above those set out in BS 7671 and the associated guidance. This may require a means of measuring solar radiation for larger installations if radiation levels are changing during testing.
Simultaneous monitoring of the solar radiation can present practical difficulties unless the system has a radiation sensor installed and its cable is accessible at the place where testing is carried out. If radiation conditions are reasonably constant (ie no sudden obscuring of direct sunlight by clouds), comparing one open-circuit string voltage with another will identify faulty strings.
Guidance on commissioning tests can also be found in appendix C.
As noted in section 2.4.1 in order to satisfy the requirements of the distribution Network Operator, various tests and documentation needs to be provided. See section 1.4 and 2.4.1 for more details on the process to be followed depending on the size of system.
Compliance with DNO requirements will include:
● Inverters should be programmed such that the automatic protection system operates at :
■ Operating voltage greater than 264 V phase to neutral
■ Operating voltage less than 207 V phase to neutral
■ Operating frequency greater than 50.5 Hz
■ Operating frequency less than 47 Hz
● Dual supply labelling should be provided at the service termination, meter position and all points of isolation to indicate the presence of on-site generation and indicating the position of the main a.c. switch disconnector(for suitable label see ER G83/1 or see the sample reproduced in ‘Example Signs’ and on the back cover of this guide).
● At the point of interconnection, the following information is to be displayed (typically all displayed on the circuit diagram):
■ Circuit diagram showing the relationship between the inverter equipment and supply.
■ A summary of the protection settings incorporated within the equipment.
■ A contact telephone number for the supplier/installer/maintainer of the equipment.
NB It is also good practice for shutdown and start-up procedures to be detailed on this diagram.
Note: the requirements for larger systems connected under G59/1- including commissioning tests (which may need to be witnessed) are to be confirmed with the relevant DNO engineer as part of the connection application process.
4.4 Labelling Requirements for labelling are contained within the relevant sections of this guide. Example labels can be seen below.
Do not disconnect d.c. plugs and sockets under load - turn off a.c. supply first.
PV system - main a.c. isolator.
Do not work on this equipment until it is isolated from both mains and on-site generation supplies
✓ The user manual should include as a minimum the following information:
● A copy of the basic system information
● A single line electrical schematic.
● A copy of the manuals and data sheets for the following system components:
■ Other relevant product documentation.
Test results & commissioning data
● A copy of the test & commissioning documentation
● Table of inverter protection settings (under/over voltage, under/over frequency, etc).
Operation & maintenance data
● Procedures for verifying correct system operation.
● A checklist of what to do in case of a system failure.
● Shutdown/isolation and startup procedures.
● Maintenance & cleaning recommendations
● Considerations for any future building works adjacent to the PV array (eg roof works) to avoid potential damage or shading of the PV array.
G83/1 INSTALLATION COMMISSIONING CONFIRMATION FORM This form is courtesy of the Energy Networks Association (ENA) and can be downloaded from www.energynetworks.org/word/ER_G3-1_Appendix_3.doc
Engineering recommendation G83/1.SSEG installation commissioning confirmation Confirmation of commissioning of a SSEG unit connected in parallel with the public distribution network - in accordance with Engineering Recommendation G83/1. One Commissioning Pro-forma per installation is to be submitted to the DNO.
Property address
Customer supply number
SSEG owner
SSEG details
Serial number of SSEG
Serial number/version numbers of software
SSEG rating (A) and power factor
Maximum peak short-circuit current
Location of SSEG unit within the installation
Location of multi pole isolator
Address
Final copy of system schematic
SSEG Test Report (Appendix 4) or web address if appropriate
Computer print out (where possible) or other schedule of protection settings
Electricity meter(s) make and model
Declaration - to be completed by installer
The SSEG installation complies with the relevant sections of Engineering Recommendation G83/1
Protection settings have been set to comply with Engineering Recommendation G83/1
The protection settings are protected from alteraton except by prior written agreement between the DNO and the Customer or his agent
Safety labels have been fitted in accordance with section 6.1 of Engineering Recommendation G83/1
The SSEG installation complies with the relevant sections of BS 7671 and an installation test certificate is attached
Comments
This safety Certificate has been issued to confirm that the electrical installation work to which it relates has been designed, constructed and inspected and tested in a cordance with British Standard 7671 (The IEE Wiring Regulations).
You should have received an original Certificate and the contractor should have retained a duplicate Certificate. If you were the person ordering the work, but not the user of the installation, you should pass this Certificate, or a full copy of it including the schedukes, immediately to the user.
The ‘original’ Certificate should be retained in a safe place and be shown to any person inspecting or undertaking further work on the electrical installation in the future. If you later vacate the property, this Certificate will demonstrate to the new owner that the electrical installation complied with the requirements of British Standard 7671 at the time the Certificate was issued. The Construction (Design and Management) Regulations require that for a project covered by those Regulations, a copy of this Certificate, together with schedules is included in the project health and safety documentation.
For safety reasons, the elcetrical installation will need to be inspected at appropriate intervals by a competent person. The maximum time interval recommended before the next inspection is stated on Page 1 under “Next Inspection”.
This Certificate is intended to be issued only for a new electrical installation or for new work associated with an alteration
or addition to an existing installation. It should not have been issued for the inspection of an existing electrical installation.
A “Periodic Inspection Report” should be issued for such a periodic inspection. The Certificate is only valid if a Schedule of
Inspections and Schedule of Test Result are appended.
PV COMMISSIONING TEST SHEETS Note: This form is subject to change as it is being worked on in the IEC Technical Committee
PV system - Installation Check List
General installation
Equipment compliant with standards, correctly selected & not damaged Equipment accessible for operation, inspection & maintenance Equipment and accessories correctly connected Particular protective measures for special location Equipment and protective measures appropriate to external influences System installed to prevent mutual detrimental influence Conductors connected and identified Conductors selected for current carrying capacity and voltage drop Conductors routed in safe zone or protected against mechanical damage Presence of fire barriers, seals and protection against thermal effects
General installation
Ventilation provided behind array to prevent overheating / fire risk Array frame & material corrosion proof Array frame correctly fixed and stable; Roof fixings weatherproof Cable entry weatherproof
Protection against overvoltage / electric shock
Live parts insulated, protected by barrier / enclosure, placed out of reach or Class II Array frame equipotential bonding present (only relevant if required) Surge protection devices present (only relevant if required) RCD provided (only relevant if required) Frame correctly integrated with existing LPS installation
Physical separation of a.c. and d.c. cables d.c. switch disconnector fitted (to IEC<PHONE>.2.2) d.c. cables - protective and reinforced insulation (only relevant if required) All d.c. components rated for operation at max d.c. system voltage (Voc stc x 1.25) PV strings fused or blocking diodes fitted
a.c. isolator lockable in off position only Inverter protection settings to local regulations
d.c. system
General labelling of circuits, protective devices, switches and terminals (to IEC60364-6-61) PV system schematic displayed on site Protection settings & installer details displayed on site Emergency shutdown procedure displayed on site a.c. isolator clearly labelled d.c. isolator / junction boxes suitably labelled Signs & labels suitably affixed and durable
PV Array Test Report - d.c. circuits
oc
sc
d.c. Rating
Connected to inverter
Array insulation Resistance Ref IEC 60364-713-04 Test method: Annex-1
Pos – Earth
Neg – Earth
Read and make sure you understand this procedure before you start any work.
Insulation testing is an electric shock hazard - use caution when performing the testing.
Do not perform the test before you have received practical training.
Limit the access to the working area.
Do not touch and take measures to prevent any other persons to touch any metallic surface with any part of your body when performing the insulation test.
Do not touch and take measures to prevent any other persons to touch the back of the module/laminate or the module/laminate terminals with any part of your body when performing the insulation test.
Whenever the Insulation test device is energised there is voltage on the testing area. The
equipment is to have to have automatic auto-discharge capability.
● Two test methods are possible:
● Where the structure/frame is bonded to earth, the earth connection may be to any suitable earth connection or to the array frame (where the array frame is utilised, ensure a good contact and that there is continuity over the whole metallic frame).
● For systems where the array frame is not bonded to earth (eg where there is a class II installation) a commissioning engineer may choose to do two tests: i) between Array cables and Earth and an additional test ii) between Array cables and Frame.
● For Arrays that have no accessible conductive parts (eg PV roof tiles) the test should be between Array cables and Building Earth
Test Zone Preparation:
Limit access to non-authorized personnel.
Isolate the PV array from the inverter
Disconnect any piece of equipment that could have impact on the insulation measurement (i.e. overvoltage protection) in the junction or combiner boxes.
● Insulation resistance test device
● Insulation gloves
● Safety boots.
● short-circuit box
Separate tests to Array positive and Array negative
- Voc stc
(min. 100V) **
** Test voltage adjusted to prevent peak voltage exceeding module or cable rating
● BS 7671: 2001 ‘Requirements for Electrical Installations, IEE Wiring Regulations’, Sixteenth Edition (incorporating Amendments), ISBN: <DIGITS>, www.iee.org/publish/books/WireAssoc
● IEE Guidance Note 7 - Special Locations, (2nd Edition), ISBN <DIGITS>, www.iee.org/publish/books/WireAssoc Note: IEE Guidance Note 7 - Special Locations, Chapter 12 covers ‘Solar photovoltaic (PV) power supply systems’ as a ‘special location’ as defined in IEE Regs. The guidance is based on IEC 60364-7-712: ‘Requirements for special installations or locations – Solar photovoltaic (PV) power systems’.
● Part P (Electrical safety) - Building Regulations,
Note: From 1st January 2005, people undertaking electrical work in homes and gardens
in England and Wales have had to follow new rules in Building Regulations. Virtually all
domestic PV installations will fall under the scope of Part P. There are two routes to comply with the requirements of Part P:
• Notify the relevant Building Control department before starting the work
• The contractor registers under a Competent Person Scheme
Note: An electronic version of the form is available at the Local Authority Building Control (LABC) website www.link2content.co.uk/uploads/buildingnotice%202005%20unprotected (1).doc, and it can be submitted using their ‘Submit-a-Plan’ scheme www.labc-services.co.uk/buildingregs/default.asp.
● Engineering Recommendation G83/1: Sept 2003, ‘Recommendations for the connection of Small-scale Embedded Generators (up to 16A per phase) in parallel with Public Low-Voltage Distribution Networks’, (Energy Networks Association, 2003),
Note: This simplified connection route applies to ‘type tested’ inverters for systems up to
about 5kVA per phase (see sect 2.4.1). Prior-notification of the Distribution Network Operator (DNO) is not required for ‘single’ installations, but is required for ‘multiple’ single phase installations. It refers to the Electricity Safety, Quality and Continuity Regulations (ESQCR), 2002. Draft prEN 50438 ‘Requirements for the connection of micro-cogenerators in parallel with public low-voltage distribution networks’ is
a European version, which once issued, will also cover systems up to 16A
● Engineering Recommendation G59/1, ‘Recommendations for the connection of Embedded Generating Plant to the Regional Electricity Companies’ Distribution Systems’, (Electricity Association, 1991), www.energynetworks.org/dg01.asp Note: This is the Electricity Industry Recommendation for connection of generators. It is applicable if the inverter is not covered under G83/1.
● IEC 61215 Building Control Approval ‘Crystalline silicon terrestrial photovoltaic (PV) modules – Design qualification and type approval’, www.iec.ch Note: This is the International standard for crystalline PV. It specifies requirements for the design qualification and type approval of terrestrial photovoltaic modules suitable for long-term operation in general open-air climates, as defined in IEC 60721-2-1. It
determines the electrical and thermal characteristics of the module and shows, as far as possible, that the module is capable of withstanding prolonged exposure in certain climates.
● IEC 61646 ‘Thin film terrestrial photovoltaic (PV) modules – Design qualification and type approval’, www.iec.ch Note: This is the International standard for thin film PV. It specifies requirements for the design qualification and type approval of terrestrial thin-film photovoltaic modules suitable for long-term operation in moderate open-air climates.
● IEC 61730-1 ‘Photovoltaic (PV) module safety qualification - Part 1: Requirements for construction & IEC 61730-2 ‘Photovoltaic (PV) module safety qualification - Part 2: Requirements for testing’, www.iec.ch Note: Part 1 is Fundamental construction requirements, Part 2 is Testing requirements. These two international standards specify requirements for photovoltaic modules in order to provide safe electrical and mechanical operation during their expected lifetime. They address the prevention of electrical shock, fire hazards, and personal injury due to mechanical and environmental stresses. Pertains to the particular requirements of construction and is to be used in conjunction with IEC 61215 or IEC 61646.
● IEC61215 Building Control Approval, www.odpm.gov.uk/index.asp?id=1130474, www.labc-services.co.uk/buildingregs/default.asp Note: For ‘integrated products’ in the UK where the PV forms part of the building
envelope (eg PV roof tiles), proof of compliance with relevant Building Regulations may be required by the local Building Control Inspector, eg compliance to:
• Fire resistance standards
● PPS22 ‘Planning Policy Statement 22: Renewable Energy, ISBN <DIGITS>, 2004,
Note: UK Planning Consent (if required). PPS22 replaces UK Planning Policy Guidance note (PPG)22. It sets out the Government's planning policies for renewable energy, which planning authorities should have regard to when preparing local development documents and when taking planning decisions. Also see ‘Planning for Renewable Energy; A companion Guide to PPS22’, which provides additional guidance for PV in Technical Annex 6 Active Solar (Photovoltaics), ISBN <DIGITS>.
● BRE Digest 489 – ‘Wind loads on roof-based photovoltaic systems’, ISBN <DIGITS>, 2004, www.brebookshop.com Note: This Digest reviews the wind loading information appropriate for roof-based PV systems and gives recommendations and guidance for the design of roof-based PV systems for wind loads. It covers both PV tiles or slates integrated into pitched roofs and PV modules mounted on or above pitched roofs.
● BRE Digest 495 – Mechanical installation of roof-mounted photovoltaic systems, ISBN <DIGITS>, 2005, www.brebookshop.com Note: This Digest gives guidance on installing and using photovoltaic systems on roofs. The guidance refers only to the mechanical installation of roof mounted integrated and stand-off photovoltaic systems; it provides best practice guidance on installation requirements and does not constitute fixing instructions.
‘Photovoltaics in Buildings – Safety and the CDM Regulations’, (BSRIA/DTI Feb 2000, ISBN <DIGITS>), www.bsria.co.uk/bookshop/system/index.html Note: This covers larger systems, although most of the safety advice is also relevant to small installations that may be exempt from the Regulations. It provides a simple guide to the Construction Design and Management Regulations 1994 (CDM Regulations), with regard to the design, installation, operation, maintenance, decommissioning and disposal of PV installations in buildings. It also provides a commentary on the UK legislative framework with particular reference to CDM Regulations, hazards and risks associated with PV installations, and PV issues that must be addressed in the Health and Safety Plan and Health and Safety File.
Draft IEC 62446 Ed.1 ‘Grid connected PV systems – Minimum system documentation, commissioning tests and inspection requirements’. Note: This standard will define the minimum information and documentation required to be handed over to a customer following the installation of a grid connected PV system. This document also describes the minimum commissioning tests, inspection criteria and documentation expected to verify the safe installation and correct operation of the system. This document is not written for AC module systems or systems that utilize energy storage (e.g. batteries) or hybrid systems.
Guide CE72 ‘Installing small wind-powered electricity generating systems’, Energy Efficiency Best Practice in Housing, 2004 Note: A companion Guide for small wind systems 500W to 25kW.
Draft IEC 62257-7-2 Technical Specification: ‘Recommendations for small renewable energy and hybrid systems for rural electrification – Part 7-1: Generators – Photovoltaic arrays Note: This is a draft Technical Specification not a Standard, but includes much useful guidance and explanation of international best practice for installation of PV systems.
BS 6133:1995, ‘Code of practice for Safe operation of lead-acid stationary batteries’ Note: This includes guidance on design, operation & maintenance of battery systems.


Rayman Origins is a very nice platform game!
!
This game is just so funny!


Home » About WA1
The objective of WellAware1 is to present the facts about current events that are usedhroughout history, we the people have been lied to by our leaders. This is a fact. Lives have been lost due to these lies. That is also a fact. When we see events unfold on TV, that is immediately used to further a political agenda. Any unanswered questions about things that don’t make sense must be answered before we can expect to move forward as a nation.
What we have discovered through the past 4 years of our investigation of the news, and historical events, is that they are either partially influenced, completely scripted out, or fictional but claimed to be factual and produced by the same individuals. When scripted out they will employ actors who are related to approximately 5-8 families. These families have been at the core of historical events since the beginning of this nation and more than likely longer. They are the owners of the media conglomerates and passd use their connections to continue propagating their lies. They use pseudonyms and straw families to generate the character they need to play the roles as our elected officials and benefit by the lies they generate. When caught, they simply kill off the character and change roles and the pseudonym use make it impossible to track them down and hold them accountable-cast.
Rather than fight amongst each other, focus your intentions on getting the legislation changed that will finally close the loophole that allows a person to have a third party individual vouch for their identity, and never have to show any form of ID to run for the office of an elected official. On top of that, they are legally permitted to use a pseudonym name that is not registered to their Vince of Pantera
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Same BS Different Country...


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Probing the initial stages of heavy ion collisions with direct photons at PHENIX / Esha, Roli (speaker) ()
Direct photons are emitted unscathed from all the stages of the relativistic heavy ion collisions and therefore are an excellent probeas they do not interact strongly with the medium. PHENIX has already measured a direct photon excess in Au+Au collisions at 200 GeV in the low momentum region with respect to p+p collisions. [...]
2021 - 0:18:00. Conferences; Initial Stages 2021 External links: Talk details; Event details In : Initial Stages 2021
Nonperturbative properties of overoccupied gluonic plasmas / Boguslavski, Kirill (speaker) (Vienna University of Technology (AT))
In ultrsome fascinating phenomena of QCD. [...]
Dynamical initialization of hydrodynamics for heavy-ion collisions at Beam Energy Scan energies / Du, Lipei (speaker) (The Ohio State University)
At Rn (BES) energies, the dynamics of the pre-hydrodynamic stage and the effects from a nonzero net baryon current become essential. We develop a (3+1)-dimensional initial stage model for both energy-momentum and the net baryon current, as dynamical initial conditions for a hydrodynamic evolution module, before the colliding nuclei interpenetrate and the produced system gets completely hydrodynamized. [...]
Observation of impact parameter dependence of $\mu^{+}\mu^{-}$ acoplanarity in ultra-peripheral PbPb collisions / Yang, Shuai (speaker) (Rice University)
The CMS Collaboration reports on new differential measurements of $\gamma\gamma \rightarrow \mu^{+}\mu^{-}$ production in ultra-peripheral PbPb collisions at $\sqrt{s_{\rm NN}}$ = 5.02~TeV, using data collected during the 2018 LHC run with an integrated luminosity of 1.5~nb$^{-1}$. Photon-photon interactions have been observed in hadronic heavy-ion collisions by STAR and ALTAS experiments at very low transverse momentum ($p_T$) regions and the measured $p_T$ and azimuthal angular correlations of lepton pairs via $\gamma\gamma$ scattering in hadronic events exhibit significant broadening compared to that from vacuum production in ultra-peripheral events. [...]
Invited: Recent developments in UPC / Cole, Brian (speaker) (Columbia University (US))
Invited: MPI in HI / Gaunt, Jonathan Richard (speaker)
Dynamical modeling of the initial energy-momentum and baryon charge distributions for / Shen, Chun (speaker) (Wayne State University)
Building upon Ref. [1], we present an improved three-dimensional dynamical initialization model for heavy-ion collisions, implementing local energy-momentum conservation and baryon charge fluctuations at string junctions [2] [...]
Probing heavy quark dynamics via multiparticle azimuthal correlations of D0 mesons in PbPb collisions at 5.02 TeV / Zhang, Liuyao (speaker) (Rice University (US))
In this presentation, we show measurements of the second Fourier coefficient of the azimuthal distribution (elliptic flow, v2) of prompt D0 and D0bar mesons using the four-particle cumulants technique at midrapidity (|y| < 1). These measurements are performed using data from PbPb collisions at 5.02 TeV collected by the CMS detector at the LHC in 2018. [...]
First measurements of genuine three-harmonic correlations in Pb-Pb collisions with ALICE / Mordasini, Cindy (speaker) (Technische Universitaet Muenchen (DE))
Multiparticle azimuthal correlations have proved their usefulness to study andRecently, the event-by-event correlated fluctuations between two different flow amplitudes have been measured using Symmetric Cumulants. [...]
Low-mass dielectron measurements with ALICE at the LHC / Meninno, Elisa (speaker) (Stefan-Meyer-Institut für subatomare Physik, Vienna)
Dileptons and photons are unique tools to study the space-timed continuously by a variety of sources, in particular prompt and thermal photons and semi-leptonic heavy-flavour hadron decays, during the entire history of the collision and traverse the medium with negligible final state interaction. [...]


Packers left tackle David Bakhtiari tore his ACL during a late-December practice, keeping him out of Green Bay’s postseason run.


Emotional Vs. Physical Hunger: 4 Ways to Tell the Difference - Eating Mindfully | Mindful Eating | Dr. Susan Albers | Author
April 22, 2015 By Dr. Susan Albers No comments yet
It’s not easy to know the difference between physical and emotional hunger. When you have a craving for something sweet and gooey like a chocolate chip cookie or a cinnamon roll it could be:
B) A signal that you are bored and in need of a distraction.
How can you tell? These two hunger pangs often feel exactly the same as I explain in detail in my new book 50 More Ways to Soothe Yourself Without Food (Pre-order bonuses are still available). It is like when the eye doctor asks you which image is clearer, “A” or “B” and they look exactly the same.
1) Satisfaction vs. Relief
Test: Place your hand on the part of your body that needs attention. Does it go to your stomach because it is rumbling? Or, does it go to your brain that feels dull and bored?
Fix: Aim to satisfy the part of your body that your hand rests on. If your brain is bored, give it some mentally stimulating material. If your hand traveled to your shoulders, lift and release your shoulders five times to relax your muscles. If it lands on your stomach, mindfully choose a nourishing food.
2) Emotional vs. Physical Hunger
Am I eating in response to physical hunger (rumbling stomach, low energy, etc.) or am I feeling scared, frustrated, overwhelmed or happy?
Test: Ask yourself, “How physically hungry am I on a scale from 1-10 (1=starving, 5=satiated 10=stuffed)?” If you are a 1-5, it’s likely that you do need something to eat. If so, that is okay. If you answer 6-10, it’s likely that food isn’t going to help a bit.
3) Nutritious vs. Palatable
4) Lifelong vs. Transient
Am I building a healthy relationship with food vs. anxiety, guilt or fear.
Fix: Mindful eating can help you build a healthy and balanced relationship with food. Use the 5 S’s of Mindful Eating no matter what you are eating 1) Sit down 2) Slowly Chew 3) Sense—taste, smell, listen 4) Savor-enjoy 5) Smile (pause before taking another bite). Remember it’s okay to eat the foods you love, as long as you do it mindfully!


, -3.11 min; 95% CI, -6.67 to 0.45), early seizure cessation (relative risk, 1.09, 95% CI, 0.95-1.26), or late seizure cessation (relative risk, 1.05; 95% CI, 0.93-1.18). Adverse event outcomes were limited by low event numbers. We found low certainty evidence for less respiratory depression with levetiracetam (relative risk, 0.28; 95% CI, 0.12-0.69). CONCLUSIONS: The efficacy of levetiracetam is comparable with phenytoin or fosphenytoin in children with benzodiazepine-refractory status epilepticus (low certainty evidence). Levetiracetam may cause less respiratory depression. Clinicians and guideline developers should weigh safety profiles when choosing between these agents. </s> EN-B-05142021 </s> T“”’s behalf.
“Members”e s in using the whole or part of the information or damages due to errors, faults or omissions.
Users shall agree to the privacy policy of The website. </s> Source: NDTV Education
Tokyo Olympics gold medalist Neeraj Chopra and other athletes will visit schools across the country and interact with students on various topics, including balanced diet, fitness and sports, a government statement said.
Olympians will visit schools r, 75 years of Indian Independence. Prime Minister Narendra Modi had earlier this year, during an interaction with Tokyo Olympians, asked each of them to visit 75 schools.
“,” the Ministry of Youth Affairs and Sports said.
Following Mr Chopra, Ta visit
Among the Paralympians, Avani Le join the campaign.
The campaign has been Register Before </s>. She had opportunities to become an idol-pop artist through her job working at a maid cafe in Akihabara, but she decided to avoid this conventional route into entertainment due to her lack of dancing skills.
Instead, Hikari, who asksreasons, chose a digital path that’s becoming more common. YouTubers and other artists covering Japanese songs — whether they be fan projects such as Korean duo Darlim & Hamabal, organized efforts from labels such as Tokimeki Records, or hybrids like Indonesian singer Rainych Ran — are spreading Japanese music farther than ever before, both thanks to the type of music that grabs the spotlight and how the songs are distributed.
“The adults and teens who love anime are now discovering more about Japanese music and culture as a whole,” according to a post on the Spotify blog explaining an increase in streams of anime songs, with the themes from shows like “Attack on Titan” and “Jujutsu Kaisen” performing well on streaming viral charts. Access — once a challenge for Japanese music across the board — has become much easier.
Jk up. But as online entertainment, Singing Cosplayer Hikari has found a niche whetting people’s appetitehe elegant outfits and picturesque settings also come off like a modern take on the classic enka video.
“I’m just preparing right now,” Hikari says when we talk on a Friday afternoon weeks before the event, with what kind of cosplay she will sport being an immediate thought.
Hikari’s experiences offer a homegrown case for the importance of making sure songs are accessible on the platforms people gravitate to, something the savvier companies have figured out. Shed.
Vocaloid tracks make up a large percentage of the covers appearing on Singing Cosplayer Hikari, while avatars from that world — primarily Hatsune Miku — have served as inspiration for her cosplay, as featured in images and videos. This actually proves to be a rarity for Hikari — though “cosplay” appears in the title of her channel, the bulk of her content shows her wearing traditional Japanese kimono rather than anything referencing famous characters. That wasn’t the original plan, though.
s


The card stated the authorization would be irrevocable for one year and would automatically renew on a yearly basis, unless the employee gave written notice to the union during a specified 10-day window prior to expiration each year. The card also stated, “For tand assignment, I hereby waive any right I may have to resign my union membership.”
The advice memo concluded the inclusion of the waiver of membership resignation in the dues authorization card violated the Act. It acknowledged the Board has yet to decide whether an employee can voluntarily waive their right to resign from membership. However, the Division of Advice stated that, even assuming they can, a union cannot place “too great a restriction on the ability of employees to revoke such waivers.”


Experience the best of Thai hospitality, beauty of Koh Samui and contemporary comforts at this innovative lounge restaurant, where every wish of guest is treated a command. Marvelous design, lavish décor and plush furnishings make the place plush and snug beyond imagination. Rooftop private restaurant and lounge serves delicious fusion food and tapas with sparkly cocktails accompanied by music and panoramic views. Villa offers the services of a personal butler and features LCD TV, internet, music system and refrigerator.
9Gems Lounge Restaurant has an alfresco bar where you can sip on one of our best cocktails. We also provide rooftop private dining with 360 view.
A modern, over-the-top luxury villa in a unique hilltop location offering the most beautiful and dramatic views of Koh Samui.


During the month of March you will find simple recipes that can help you plan meals for the hectic week ahead. We’ve already shown you three recipes you could quickly and easily make with slow cooker shredded chicken. This week, pot roast is the star of our meal planning show. Make beef pot roast on slow cooker Sunday and put a few twists on the classic dish throughout the week.
Growing up, we would visit my grandparents house and could always expect something to be on the stove. My favorite visits were the days my grandfather had his famous (to us) homemade marinara sauce simmering away on the stovetop. He would keep a warm baguette next to saucepan and we’d taste test (day-long taste tests are a thing, right?) until the sauce was just right – or gone.
Fortunately, this stovetop meat sauce doesn’t require an all-day simmer, but it’s sure to be one of your new go-to weeknight meals. In a large skillet over medium-high heat, cook carrots, onions, celery, and garlic. Then reduce the heat and add your family’s favorite store-bought marinara sauce (this is a real time saver), the pre-made pot roast from the weekend, salt, and oregano. Heat the sauce through for about 10 minutes and presto – a hearty meat sauce.
While my family would gladly enjoy this meat sauce with a chunk of warm bread, for a more substantial meal pour it on top of your favorite pasta or egg noodles. Plan ahead to use pot roast and some fresh vegetables to easily upgrade store-bought marinara into something special.
Quick and Easy Beef Meat Sauce
2 cups shredded cooked beef
1 package (1 pound) egg noodles, cooked
In a large skillet over medium-high, heat oil. Add carrots. Cook until carrots are slightly tender, about 4 minutes. Stir in onions, celery and garlic. Cook until tender, about 4 minutes longer.
Reduce heat to medium. Stir in marinara sauce, beef, oregano and salt. Cook until heated through, about 10 minutes.
Serve over noodles and top with Parmesan cheese.
egg noodles meal plan meal planning meat sauce parmesan pasta ragu roast beef
Easy Chicken & Rice Soup
Pot Roast Po Boys


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Learn more about our offerings at The Center for Autism.


Prior to 1952, the only real place for a professional gypsy musician to perform for a living was in a local drinking establishment. But then a native Hungarian with big dreams came along and changed all of that. Gyula Farkas established the now prestigious Rajko Music School of Romani performing arts in order to professionally train young gypsy musicians and dancers from the tiniest remote villages in Hungary, Slovakia, Romania, and the Ukraine. Only a very select group of young people are invited to Budapest to come study at this very special school from the tender age of eight until they are eighteen or nineteen years of age and well prepared to perform as members of professional ensembles of all sizes in the best of entertainment venues all over the world. The key to the students’ success, especially with respect to their amazing technical proficiency, is a constant exposure to an extensive training regimen centered around their natural inate ability to improvise music.