# Interest group forums > Electrical Contracting Industry Forum >  COC for PV installation

## Andreviljoen

Is there any limitation on what type of Tester may issue a COC for a PV installation, besides the obvious single or three phase, etc.

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## AndyD

No, any person who qualifies to issue electrical CoC's can certificate a PV installation.

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## GCE

Large portions of the PV installation will be DC voltage - According to Annex M in SANS 10142-1 pg 355 it will need to be an Installation or Master Electrician.

Single phase tester cannot sign off on DC work , or 2 phases

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AndyD (06-Oct-18)

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## AndyD

So if there's a string of DC PV panels connected to an inverter the electrical installation is no longer classed as single phase, it would be classed as a DC installation?

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## GCE

Hi Andy 

The original question was over signing PV installation off - Then Annex M would apply 

With the change in question and a single phase tester gets called to carried out a test and inspection with the view to issuing a COC on a domestic dwelling, single phase,  of which there is a PV installation - I would say that he cannot issue a coc for the complete installation and would need to exclude the PV section - The COC then would not be valid for that installation as you have now left out a critical section of the installation.

The single phase tester would be committing fraud by informing the owner he is registered to test and inspect the installation - My opinion.

Technically the majority of inverters produce 2 phases and the neutral only comes into play once you earth the one phase , as a supplier of electricity for that section. So I would say that he cannot sign off on the circuits fed from the output side of the inverter.

If I go back in my memory bank , and I cannot find the original definition of single phase tester - I do know that it has changed substantially.
Originally a single phase tester was created because the proposed quantity of RDP houses to be built would have been hampered due to the shortage of installation electricians to sign off.If I remember correctly a SPT was only allow to sign off on a supply lower than 63 amp's and a dwelling of 100 sqm - He was not allowed to sign off on low voltage downlighters, Aircons , Spa baths and a couple of other stipulations where included.It has slowly been changed over the years - The SPT does not need to pass SANS 10142 and they keep pushing the boundaries like every regulation in South Africa is pushed.
I believe that there is a place for SPT but that the scope has been allowed to creep to far and probable needs to be looked at and restricted by definition.

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## ACEsterhuizen

I respectfully disagree. PV Panels and its wiring is not a point of control as defined in the regs. Therefor it is not part of an electrical installation as defined.

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## GCE

Hi 

Not sure I fully understand your reasoning behind your above statement .

Sans 10142-1 applies from point of control on wards - We both agree 

*Point of control* - point at which a consumer can switch off the electrical installation from the electricity supplied from the _point of supply_ - We both agree but you need to include the definition,  point of supply 
*Point of supply* - point at which a supplier supplies electricity to any premises 

If we take all domestic installations and the majority of commercial installations , the PV panels/inverter will be connected after the point of control and would therefore be part of the electrical installation.

There are installations where the PV panel / inverter will be connected before the point of supply/control and then I suppose technically the area becomes grey as no COC needs to be issued.But these are big installations where arrangements are made with the municipalities and Eskom under separate agreements of which I do not know too much about.

SANS 10142-1 has a complete section 7.12 Alternative Supplies( pg 244 to 250)  and specifically mentions PV installations and deals with issues around PV installations - 7.12.7.2 states the DC component of PV systems shall comply to 7.15 , DC Installations ( pg 256)

I don't see how the statement can be made that PV is not part of an electrical installation and would not form part of the COC when SANS 10142-1 incorporates PV within the regulations.

Am I missing something ?

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## AndyD

> .....
> With the change in question and a single phase tester gets called to carried out a test and inspection with the view to issuing a COC on a domestic dwelling, single phase,  of which there is a PV installation - I would say that he cannot issue a coc for the complete installation and would need to exclude the PV section - The COC then would not be valid for that installation as you have now left out a critical section of the installation......


I'm not very clued up on the scope of a Single Phase Tester to be honest but from what you say the same logic would apply if the premises had a light circuit with normal LED lighting that was supplied by a CC or CV driver. This would also exclude him from being able to certify the installation because of the DC component whereas if that same circuit was ELV halogens (12VAC) he'd be able to sign it off.....

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## GCE

Hi 

The COC ends at the light point and excludes the light fitting besides the safety around the light fitting itself - Suppose it would be excluded and would allow the single phase tester to sign off.

I would think that the input terminals of the driver would be the light point  - The other way around it would be to install a 5 amp socket and plug the driver in.The socket would be the point.

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## ACEsterhuizen

can you switch off or control the pv panels at the "point of Control" in any way, If yes, then I agree. If no, then it falls outside this definition and cannot be "certified" by a CoC.




"Point of control - point at which a consumer can switch off the electrical installation from the electricity supplied from the point of supply - We both agree *but you need to include the definition, point of supply*"

You decided that, that must be included in the definition, but it is not as it is written in the regs?

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## GCE

The "point of supply "definition is in the regulations 

I am going to start at the beginning - I have listed definitions of what I see as relevant - Definitions , in red, are from the OHSA , Electrical Installation regulations 2009 ( the definitions are copied from the regulations and not my making ) 
The OHSA is what gives SANS 10142-1 teeth 

electrical installation means any machinery, in or on any premises, used for the transmission of electricity from a point of control to a point of consumption anywhere on the premises, including any article forming part of such an electrical installation irrespective of whether or not it is part of the electrical circuit, but excluding
(a)
any machinery of the supplier related to the supply of electricity on the premises;
(b)
any machinery which transmits electrical energy in communication, control circuits, television or radio circuits;

point of control means the point at which an electrical installation on or in any premises can be switched off by a user or lessor from the electricity supplied from the point of supply, or the point at which a particular part of an electrical installation on or in any premises can be switched off where different users occupy different portions of such premises;

point of supply means the point at which electricity is supplied to any premises by a supplier;

supplier in relation to a particular electrical installation, means any person who supplies or contracts or agrees to supply electricity to that electrical installation;


One relevant part of the electrical installation definition is - including any article forming part of such an electrical installation irrespective of whether or not it is part of the electrical circuit,
This allows us as Electrical contractors to be in charge of installing cable trays , conduits etc  and is relevant to the PV installations as well 

Moving onto SANS 10142-1 - We start at the scope covered - Again regulations copied are in red , not mine 

1.2 Aspects covered by this part of SANS 10142
This part of SANS 10142 covers
a) circuits supplied at nominal voltages up to and including 1 000 V a.c. or
1 500 V d.c. The standard frequency for a.c. is 50 Hz. The use of other
frequencies for special purposes is not excluded,
b) circuits, other than the internal wiring of apparatus, that operate at
voltages exceeding 1 000 V and are derived from an installation that has
a voltage not exceeding 1 000 V a.c.,
c) any wiring systems and cables not specifically covered by the standards
for appliances,
d) all consumer installations external to buildings,
e) fixed wiring in the power supply circuits for telecommunication equipment,
signalling equipment, control equipment and the like (excluding internal
wiring of apparatus),
f) the extension or alteration of the installation and also parts of the existing
installation affected by the existing extension or alteration,
g) fixed wiring needed to connect the various units of complex machinery
that are installed in separate locations,
h) equipment for which no standard is referenced ,
i) replacement or maintenance of components, and
j) earthing arrangements.

If we are going to refer to PV installations as machinery I would hazard a guess and say that PV is complex as describe in g above - So I would think it is covered under the scope 

Moving onto Normative references - regulations copied are in Red and not mine - I have been selective to what I see as relevant 
2 Normative references
The following referenced documents, in whole or in part, are normatively
referenced in this document and are indispensable for its application.
For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any
amendments) applies. Information on currently valid national and
international standards can be obtained from the SABS Standards
Division.

IEC 62116, Utility-interconnected photovoltaic inverters – Test procedure of
islanding prevention measures.

SANS 60364-7-712/IEC 60364-7-712, Electrical installations of buildings –
Part 7-712: Requirements for special installations or locations – Solar
photovoltaic (PV) power supply systems.

SANS 61215/IEC 61215, Crystalline silicon terrestrial photovoltaic (PV)
modules – Design qualification and type approval.

SANS 61646, Thin-film terrestrial photovoltaic (PV) modules – Design
qualification and type approval.

As can be seen from the above SANS workgroup have used PV related documents to compile SANS 10142-1 

The definitions in SANS 10142-1 that I see as relevant  - regulations copied are in Red and not mine 

3.33
electrical installation
machinery, in or on any premises, that is used for the transmission of
electrical energy from a point of control (see 3.56) to a point of
consumption (see 3.55) anywhere on the premises, including any article
that forms part of such an installation, irrespective of whether or not it is part
of the electrical circuit, but excluding
a) any machinery of the supplier that is related to the supply of electricity on
the premises,
b) any machinery that is used for the transmission of electricity of which the
voltage does not exceed 50 V, where such electricity is not derived from
the main supply of a supplier, and
c) any machinery that transmits electrical energy in telecommunication,
television or radio circuits

3.9
Certificate of Compliance
CoC
certificate that is issued by a registered person in respect of an electrical
installation or part of an electrical installation

3.56
 point of control
point at which a consumer can, on or in any premises, switch off the
electrical installation from the electricity supplied from the point of supply

3.58
 point of supply
point at which a supplier supplies electricity to any premises
From the above definitions it would appear that the machinery (PV installation ) is being used for the transmission of electrical energy after the point of control 

Now I get my COC form out and low and behold in section 2 - Installation it ask's me about alternative supplies and references me to 7.12 page 244

Is alternative power supply installed? (See 7.12):  Yes  No


7.12 Alternative supplies
NOTE Alternative supplies include but are not limited to low-voltage generating sets,
photovoltaic (PV) installations, gas generators, diesel generators, wind turbines and
hydropower plant.

7.12.1.1 Subclause 7.12 applies to an installation that incorporates
alternative supplies intended to supply, either continuously or occasionally,
all or part of the installation with the following supply arrangements:
a) supply to an installation or part of an installation which is not connected to
the main supply of a supplier;
b) supply to an installation or part of an installation as an alternative to the
main supply of a supplier; and
c) appropriate combinations of the above

Having a look at 7.12 it references in particular PV installations and then verifies that even if it feds only part of the installation it is still relevant 

7.12.1.2 Subclause 7.12 covers, but is not limited to, the following
a) alternate supply that consist of a combination of an internal combustion
engine or a turbine, hydro plant, wind energy recovery installation or any
similar source of mechanical energy and an alternator or a d.c. generator;
b) rotary UPS (uninterruptible power supply) systems that consist of a
combination of an electric motor and an alternator, with batteries as a
standby power source for the electric motor, or with an internal
combustion engine, gas or turbine as a standby power source for the
alternator; and
c) static UPS systems that consist of static inverters with batteries as the
standby power source (with or without bypass facilities).
d) installations similar to those in 7.12.1.2(c), but sourcing energy from
photovoltaics or other sources.

Again 7.12.1.2 d references in particular PV systems 
They then continue to reference in broad terms to various regulations that need to be complied to for alternative supply's - Their is then a section for additional requirements for PV in 7.12.4

7.12.4 Additional requirements for installations that incorporate
electrical supply derived from static inverters used with uninterruptible
power supply (UPS) equipment and photovoltaic installations off-grid
or on-grid

Further on there is another reference to PV and the requirements for color coding on the DC terminals 
7.12.5.2 DC conductors and battery protection methods
Colour coding for AC/DC solar/photovoltaic installations shall be in
accordance with the requirements given in 6.3.3.3.
NOTE DC circuits may be identified by means of colours or symbols.


7.12.7 Additional requirements for photovoltaic (PV) and similar
installations that provide a supply as an alternative to the main supply
7.12.7.1 The photovoltaic installation shall comply with SANS 60364-7-712
and the solar panels shall comply with SANS 61215 (for poly and mono
crystalline) or SANS 61646 (for thin-film).
7.12.7.2 The DC component of the installation shall comply with 7.15.
7.12.7.3 The rated voltage of each circuit shall be clearly indicated at all
ends of the circuit.
In the case of combined circuits, every circuit shall be easily identifiable.
Where single core conductors are used, such conductors for each circuit
shall be tied together at intervals to ensure identification, unless another
suitable arrangement is employed.
7.12.7.4 Precautions regarding parallel operation as prescribed in 7.12.6.1,
and overcurrent protection as prescribed in 7.12.4.1 shall be provided.
7.12.7.5 In addition it shall be recognised that the supply from each inverter,
battery arrangement and PV panel (or identified clustered group), constitutes
a supply, and requires arrangements similar to point of supply, which shall
include switch-disconnection arrangements and shall comply with 7.12.5.
7.12.7.6 If applicable, all exposed conductive parts may require earthing as
prescribed in 6.12.3.

In the above they reference to PV being similar to a point of supply - similar being the operative wording 
They also reference to PV systems complying to 7.15 DC Installations 

I find it difficult that after all the referencing to PV systems in the code that anybody would say that PV systems are excluded - The COC asks if there is an alternative supply and then tells you were to look and what to do - When you sign Section 3 , Inspections and tests you are signing to say that you have followed the regulations which include numerous references to PV 

Am I still misunderstanding something

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Dave A (11-Jan-19)

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## ACEsterhuizen

Thank you. I seems I am wrong. I stand corrected for now. :Slap: 

I am still confused why an INSTALLATION is defined from the* point of control to the point of consumption*. It should then read from* the point of supply*.

I will write the Chief Inspector to clear that up for me. His answer will give closure. The definition of "Installation" should then be from *the point of supply to the point of consumption*.

You quoted the reg:

_7.12.7.5 In addition it shall be recognised that the supply from each inverter,
battery arrangement and PV panel (or identified clustered group), constitutes
a supply, and requires arrangements similar to point of supply, which shall
include switch-disconnection arrangements and shall comply with 7.12.5.

and:

3.33
electrical installation
machinery, in or on any premises, that is used for the transmission of
electrical energy from a point of control (see 3.56) to a point of
consumption (see 3.55) anywhere on the premises, including any article
that forms part of such an installation, irrespective of whether or not it is part
of the electrical circuit, but excluding
a) any machinery of the supplier that is related to the supply of electricity on
the premises,
b) any machinery that is used for the transmission of electricity of which the
voltage does not exceed 50 V, where such electricity is not derived from
the main supply of a supplier, and
c) any machinery that transmits electrical energy in telecommunication,
television or radio circuits

7.16.1 General
The distribution system is that part of the installation between the point of
control connected to the point of supply where electricity is supplied by the
supply authority, and the point of control of any particular electrical
installation connected thereto, whether it is a specific user or a communal
installation, where the user of that particular installation can switch it off.

__3.56_
_point of control

_
_point at which a consumer can, on or in any premises, switch off the_
*electrical installation from the electricity supplied from the point of supply*

The inverter, battery arrangement and PV panel (or identified clustered group), constitutes a supply.

_"Disputes

10. (1) Should a dispute arise over the interpretation of a health and safety standard referred to in regulation 5(1) between a user, a registered person, an electrical contractor, an approved inspection authority for electrical installations or a supplier, as the case may be, an affected person may appeal against that interpretation to the chief inspector.
(2)
A person who refers a dispute referred to in subregulation (1) shall serve a notice of dispute, setting out fully the nature and grounds of the dispute, on both the chief inspector and the person whose interpretation he or she is disputing, by personally delivering the notice of dispute or sending it by registered post.
(3)
The person whose interpretation is disputed shall within 14 working days of the date on which he or she received the notice of dispute, forward a notice setting out the reasons for his or her interpretation to the chief inspector.
(4)
The chief inspector shall, after having considered the grounds and the cause of the dispute, confirm, set aside or vary the interpretation of the safety standard in question or substitute it for the interpretation, which in the opinion of the chief inspector, ought to have been given."_

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## ACEsterhuizen

And thank you, it sure was an interesting discussion. Pushing 60 and still learning. :Crazy:  The ambiguity is also having a field day with my OCD.

Have a good day.

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## GCE

Discussion and difference of opinion is always good as it forces all sides to relook and rethink the topic 
Never understood why they made the SANS10142-1 cover Black - The old cover that was Grey was appropriate 
I find the more I read it the more doubts I have 

*Point of supply vs. Point of control is easier to explain in an example* .

We are presently doing a small shopping centre and taking a 500Kva supply 400V from Eskom.
Eskom have there main CB and KWH meter in a kiosk with Eskom locks and fence and more locks 
We have to run the cable from the kiosk to the Centre's main LV panel 
The point of supply is not readily accessible for us to carry out a COC test at -  and so the incoming mains CB in our LV panel will be the point of control at which we can legally carry out and sign off on ( the regs are written so that we are still responsible for cable sizing and faults between point of supply and point of control) .

Eskom is the supplier and the Centre management is the consumer .

We now run cables from main LV to individual shops and stop in a surface DB with an Isolator.
Along comes the tenant and appoints a contractor to install electrical in her Biltong shop.
The contractor will not have access to the main LV room and so the regulations allow him to use the isolator as point of control and sign the COC accordingly 
The actual point of supply is Eskom and if he had to sign a COC from point of supply he would need to check the Centre's DB 
Take a big shopping centre , there could be 5 or 6 LV panels and a transformer before he gets to point of supply which will be MV 

For the Biltong shop the Centre management is effectively the supplier even though they are also the consumer in Eskom's eyes and depending where you are testing as a contractor 

Is the reason that the regulations are written in such a way that shopping centres even though they are the supplier still need to adhere to the regulations.- Comes back to the point of a PV system effectively being the supply , but still falling within the point of control , you cant be a supplier and consumer , but realistic you can - No wonder we get confused

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## Smiley

Recently decided to go grid tied. Was off-grid since 2012, on select circuits. 

Searching around, this thread popped up on Google, being one of the best ones I have read so far, as I have seen quite a few solar companies, been chatting on another forum, picking up the different beliefs (loosely used) between how the regulations are read. Grey manual reference above makes perfect sense.

So, the question is, from the regulations published, it all boils down to very specifics like only this type of equipment can be used, installed in this specific manner, using these regulation ito panel wire ... the home owner terms of reference.  :Big Grin: 

For I see this whole thing playing out into the future where more and more electricians are going to get solar trained, which in turn will help drop the prices of getting a system installed, with a CoC, even removing the current requirement of a engineer signing off. On that point. I know of a electrical engineer who charges per array wattage. 2,5kw system costs R2.5k ex, 10kw system R6750 ex. That makes a lot of sense, for getting it signed off.

But first the CoC, panels and AC side.

Being in Bellville Cape Town, does anyone know of any suitable qualified person/s here that I can chat to? 
Or can someone help me by telling me the exact requirements, in equipment terms, what must be in place, that they will sign such off, if I share what is in place?
Or refer me to the right thread if this is not the spot for that, start a specific thread on that?

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## GCE

Hi 
At the moment you do not need an engineer to sign off on Solar installations , unless you get to the really big ones that are being dealt with under REIPPP programs .
At the moment the biggest you can go is 1MV privately and I stand corrected.

In my opinion the Solar industry has been hijack to some extent by those that see it as a quick buck.

Some are also quick to say that they regulations, SANS 10142-1 do not cover DC/PV even though the Introduction in the book clearly states that it does (pasted in Red below) .
There is also misconception that the circuits between panels are control circuits when they are in fact power circuits.

*An Electrical contractor cannot sign off on a job unless he was in general control.
*
The whole solar regulation is being looked at again and it has not been decided yet if it will continue forming part of SANS 10142-1 or if a different set of regulations, SANS 10142-3 may be created.

To me the biggest problem is that the majority of people are not taking into account the various bylaws ( Fire , Structural , Municipal ) when installing and future maintenance.


Introduction
In this edition an attempt has been made to move towards the IEC codes:
extra low voltage *(below 50 V) and d.c. applications (up to 1,5 kV)* have been
introduced as new requirements owing to the extensive usage of, and
increased fire risk that result from, high load currents. This part of
SANS 10142 does not intend to cover the LV control circuits of machinery or
system components that are external circuits between separately installed
parts of the machinery or system components.
This part of SANS 10142 includes certain provisions which are for
information and guidance only. These provisions do not use the word "shall"
and they can be found in the text, in the notes and in the informative
annexes. Except in tables, notes are always for information only.
The aim of this part of SANS 10142 is to ensure that people, animals and
property are protected from hazards that can arise from the operation of an
electrical installation under both normal and fault conditions. An electrical
installation has to provide protection against

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## Smiley

> At the moment you do not need an engineer to sign off on Solar installations ...


If you connect to the grid, from the docs I read, you have to have a engineer sign it off, after getting a CoC. 
If the inverter is not on the CoCT inverter list you have even more complications. Until SABS starts "approving" stuff again ... but they are not doing it anymore I read somewhere. 

A whole lot of people bought UPS with a MPPT and promptly connected it to their DB boards. This is a huge thing as UPS / Generator to DB board connections have off-the-shelf-stock-standard-regulations. All being flaunted. Therein I think CoCT, forced by NERSA, is acting now. Deadline is 28 Feb 2019 to register all solar systems. It is a HUGE opportunity for existing electricians.

And this is not only CPT, but JHB, DBN ... all over. Everyone has the regulations in place, or are waiting on CoCT to see what transpires. Jhb the most costly for grid tied as your charges increases substantially if you connecting solar to a DB. CoCT is just the first one to enforce it publicly. If your supply is from Eskom and not a municipality, then a whole new world of challenges opens up. And if your Municipality does not have regs yet, they are coming. NERSA is behind it if you ask me. That minister did not just mention "taxes" and "solar" in that one speech with no long play in mind.

Only part where a engineer is not required is if you have a off-grid setup. For that you need to submit a wire diagram with the application to "prove" such, electrician enters the fray again. Therein me choosing to go grid-tied, cheaper, in CoCT, and you can use a pre-paid meter. Or, feed back, but that requires a meter change (+-R8500), a daily charge, lower kwh rate and a rebate at Eskom rates, ex VAT and you must not be in credit after 12 months, as it is illegal to sell power. Unless you go big. So for home users, the deck is stacked.




> In my opinion the Solar industry has been hijack to some extent by those that see it as a quick buck.


The first few quotes I got for off-grid signoff was a flat R10k+ included engineering fees. The R10k+ was based on there are NO DB board fixes required. Some tests are needed as per the form. Took the time to "train" these reputable solar installers that no, you are wrong, off-grid needs no engineer. Obviously they ignored the feedback.

A registered electrician is wot, R485 ph, give or take. Use the word "solar" in any sentence and it becomes R800 per hour minimum.

I'm persistent and kept asking for quotes, prices got better, but also more unsure the answers. I have emailed CoCT about the fiasco brewing, it has been noted.


SANS10142 is being flaunted around quite a bit, like it is used to justify installing new wires, breakers and fuses to give a CoC on the panels, yet I cannot find anything that says clearly "Solar Panel DC CoC". 

It is annoying when one thinks that most of the equipment comes with clear instructions on what fuses to use, what cable sizes and lengths (DC side), voltage drops and temp effects. Solar parts have clearly statet limits, max volts / amps / VA. Ignore that or do not fuse it properly, and their is a matter of smoke being released.





> ... various bylaws ( Fire , Structural , Municipal )


If your panels are protruding above a certain high above the highest point of ones roof, you have more costs yes. But how was your panels mounted, DIY or using a knowledgeable roof person?
Municipal regs for CoCT are quite clear. The interpretation thereof has a huge cost factor, which is not right.
Fire ... have not read one word about how to handle that. If your house is on fire with a roof full of panels and the firefighters arrive. In the USA the regs and parts required is quite clear, and their firefighters are also trained on how to work in and around solar panels. You cannot "switch" a panel of, you short them wires and it can cause impressive results. Solar panels can burn. You can cover them, that will "switch" them off.

Attached the form for CoCT, to be completed if you want to grid-tie. 
Here is CoCT info: https://savingelectricity.org.za/pv-renewables/
Other cities have same, or it is pending.

It makes sense to register all solar systems as it saves taxpayers money to identify who is not following the basic safety standards. Day someone is killed because of a DIY connection, they will throw the book at the person. There is obviously also the "other side" ito potential taxes coming to a future near you - if too many people start to use solar and some gov department decides it is losing income.

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## Smiley

Here is some more information on some of the regulations I found for JHB, DBN and NERSA.

*Eskom:* 
http://www.eskom.co.za/Whatweredoing/Documents/GAU_SMG_ FAQs.pdf
http://www.eskom.co.za/Whatweredoing...ulletinSPU.pdf

*JHB:* https://portal.segensolar.co.za/rese..._Standards.pdf

*Durban:* http://www.durban.gov.za/City_Servic...n-Process.aspx

*NERSA:* http://www.nersa.org.za/Admin/Docume...s/Consultation Paper-Rules for Registration of SSEG.pdf

*Business Insider:* https://www.businessinsider.co.za/dr...istered-2018-5

If you ask me, this is a golden opportunity for electricians all over South Africa, as they "have" the clients already. Just take that one step further and make the regulations meet the physical side.

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## Justloadit

> Fire ... have not read one word about how to handle that. If your house is on fire with a roof full of panels and the firefighters arrive. In the USA the regs and parts required is quite clear, and their firefighters are also trained on how to work in and around solar panels. You cannot "switch" a panel of, you short them wires and it can cause impressive results. Solar panels can burn. You can cover them, that will "switch" them off.


In the USA, they are demanding a firman's switch for solar panels. Solar panels do not burn on their own, as they are made from silicon and glass. There have been instances in which a cell fails and can get hot due to the current flowing through it, but this only happens on very large PV systems in which hundreds of amps are being produced by the grid. Arrays should be isolated with diodes from each other when placed in parallel, to prevent this type of failure occurring.

Arcing, because of the DC during a disconnect under full load, could cause inflammable material close by to catch alight. Correctly installed systems will not be prone to this. Proper earthing is required in the case of lightning.

However an interesting fact about misunderstandings on solar panels.
A Solar panel is known as a current source. A grid or a battery is known as a voltage source.

The difference off each is as follows :-
Current source. Irrespective of the load, provided it is with in the source voltage supply range will have a constant current from maximum load to a short circuit.
In other words a PV panel rated at 265W at midday, will provide 8.3A from 30V to 0V(short circuit). Placing a 10A fuse in series with the load, will not protect anything, as the current is constant. Off course the current is directly linked to the amount of solar radiance.

Voltage Source. Loading a voltage source will attempt to maintain the same voltage irrespective of the load, to the point that the internal impedance of the load will affect the maximum current that the voltage source can supply. This means that as the load impedance goes lower in impedance, the current will increase until something fails, such as a burning cable causing fire, or smoke coming out of your load. To protect against this failure requires an inline fuse or a circuit breaker.

Connecting mains directly on to a PV panel, will cause immediate destruction of the solar panel, and blow the mains supply fuse or circuit breaker. However properly designed equipment will never allow this situation to occur even under catastrophic failures.

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Frans400 (14-Oct-20)

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## Smiley

> Solar panels do not burn on their own, as they are made from silicon and glass. There have been instances in which a cell fails and can get hot due to the current flowing through it, but this only happens on very large PV systems ...


I once touched a solar panel where the diodes where already burnt out. Panel was melting hot. 
On Google there are pictures of panels being destroyed / burning. Maybe it is the roof structure that produces the flames? Therein my incorrect use of "panels can burn". Melt is more accurate?




> Proper earthing is required in the case of lightning.


Question: A electrician and a engineer both mentioned that earthing panels for lighting is not such a good idea, as you are supposed to use the same earth as the DB and that is just another path for some of the lightnings power, before the cable disintegrates, to get into the house. What is your take?




> However an interesting fact about misunderstandings on solar panels. A Solar panel is known as a current source. A grid or a battery is known as a voltage source.


Thank you for that.

Fuses on PV cables are to protect the wire, in case there is a short of whatever cause, correct? I prefer fuses on Pos and Neg. 
Have had a 10amp fuse installed on the wires to the panels. It burnt out when the panels reached full potential. Had to upgrade to 15amp fuse promptly, as the installer though 10amp is ample on 3 x 310w panels in series. It was a good solar day. :-) 




> Connecting mains directly on to a PV panel, will cause immediate destruction of the solar panel, and blow the mains supply fuse or circuit breaker. However properly designed equipment will never allow this situation to occur even under catastrophic failures.


I have read somewhere that you get MPPT inverters that are mounted per panel sending 220v down the wires to the central unit, which in turn is grid tied. 


Back to the question I was aiming for: Where do homeowners with grid tied solar systems stand ito of a CoC for the DB install, being AC?
Is there is CoC needed for the DC side ito panel installs?
A normal electrician cannot give on, if I read the other posts correctly. 

Batteries are straight forward, you have to have a fuse and a quick disconnect. As I want to be able to move the battery bank, it is on wheels:
Would Brad Harrison connectors (same as at the Anderson connectors) be acceptable? 
Hands are protected from the spark if you disconnect under load.

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## Justloadit

> I once touched a solar panel where the diodes where already burnt out. Panel was melting hot. 
> On Google there are pictures of panels being destroyed / burning. Maybe it is the roof structure that produces the flames? Therein my incorrect use of "panels can burn". Melt is more accurate?


Solar panels when operating at full potential can exceed temperatures above 60 degrees centigrade, and touching the surface is a sure way of burning your skin. This is one of the reasons that PV panels should have an air gap of no less than 100mm from the back of the frame to the roof. It then allows convection cooling to take place.

If you could cool the panels down to less than 25 degrees then you will get another 10% more of energy out of it. Unfortunately there is no inexpensive way to do this, so we live with the reduction of energy with the heating of the cells.




> Question: A electrician and a engineer both mentioned that earthing panels for lighting is not such a good idea, as you are supposed to use the same earth as the DB and that is just another path for some of the lightnings power, before the cable disintegrates, to get into the house. What is your take?


That is not good practice. If lightning strikes your PV panels, and you have a grid tie system, or any other system that may be running, the potential difference between the 2 earthing points could be a few thousand volts, due to the induced energy in the earth between the 2 earthed points. If you happen to be touching one of the copper water pipes, then the earth leakage is not going to save you.

Also the PV panels being on your roof, increases the risk of lightning affecting your installation.

My take on this is an earth strap from the PV panels to the shortest path to a earth via an earth spike. Then join an earth wire from the earth point on the PV panel and take it to the DB earth star point. This way there can be no potential difference between the two points, as invariably all water pipes in the house are connected to this earth, usually at the geyser position. If lightning strikes the roof or panels, it will immediately be directed to earth via the shortest path.

By joining the two earths, with a minimum of a 6mm square multi strand wire, or preferably a flat strap, then you negate this earth potential difference across the two points.




> Fuses on PV cables are to protect the wire, in case there is a short of whatever cause, correct? I prefer fuses on Pos and Neg. 
> Have had a 10amp fuse installed on the wires to the panels. It burnt out when the panels reached full potential. Had to upgrade to 15amp fuse promptly, as the installer though 10amp is ample on 3 x 310w panels in series. It was a good solar day. :-)


A brand new panel will always provide more energy that the label states, and after the first few months of operation it will drop a few watts and come close to the PV panel label. Manufacturers do this to ensure that the panel performs according to the label.

A 315W panel will produce approximately 8.75Amps at 36V on a normal day, but if there has just been a bit of rain, which has now cleared the atmosphere of dust, and dropped the temperature a bit, it causes tinny droplets in the upper atmosphere which act as little lenses, and refract and increase the sun radiance some what, with the lower temperature of the cells, you could get another 20 or so watts out of the panel, and push the current up higher, and that could be close to the fuse rupturing point.

I have seen this happen as well on a cool crisp winter morning around 10H00, by measuring the power of the panel, I was getting the full panel rating.




> I have read somewhere that you get MPPT inverters that are mounted per panel sending 220v down the wires to the central unit, which in turn is grid tied.


Grid ties inverters have galvanic insulation between the panel and mains supply, so that takes care of the isolation.




> Back to the question I was aiming for: Where do homeowners with grid tied solar systems stand ito of a CoC for the DB install, being AC?
> Is there is CoC needed for the DC side ito panel installs?
> A normal electrician cannot give on, if I read the other posts correctly.


If the panel side is below 50V, then no COC is required. However the grid ties inverter must have a SANAS approval for it to be accepted as usable equipment, and installed according to the legislation, will allow the electrician to issue a COC.




> Batteries are straight forward, you have to have a fuse and a quick disconnect. As I want to be able to move the battery bank, it is on wheels:
> Would Brad Harrison connectors (same as at the Anderson connectors) be acceptable? 
> Hands are protected from the spark if you disconnect under load.


All battery banks should have a suitably rated "DC" isolator, in order that you can disconnect the battery in case of a problem. Using an "AC" isolator or circuit breaker is extremely dangerous, as they self distruct and catch fire if the circuit is disconnected under load due to the arcing of the contacts during the disconnection. Do a google search "AC breakers in DC circuits"" to see some frightening you tubes on the failures

ANderson connectors are good, provided they are rated for your installation.

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Dave A (13-Oct-18)

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## GCE

Hi JustLoadit 

I believe your statement -_ If the panel side is below 50V, then no COC is required_ - Is incorrect - Read the Introduction to SANS10142-1 as pasted below - 

Introduction
In this edition an attempt has been made to move towards the IEC codes:
*extra low voltage (below 50 V) and d.c. applications (up to 1,5 kV) have been
introduced as new requirements* owing to the extensive usage of, and
increased fire risk that result from, high load currents. This part of
SANS 10142 does not intend to cover the LV control circuits of machinery or
system components that are external circuits between separately installed
parts of the machinery or system components.
This part of SANS 10142 includes certain provisions which are for
information and guidance only. These provisions do not use the word "shall"
and they can be found in the text, in the notes and in the informative
annexes. Except in tables, notes are always for information only.
The aim of this part of SANS 10142 is to ensure that people, animals and
property are protected from hazards that can arise from the operation of an
electrical installation under both normal and fault conditions. An electrical
installation has to provide protection against

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## Smiley

> Solar panels when operating at full potential can exceed temperatures above 60 degrees centigrade, and touching the surface is a sure way of burning your skin. This is one of the reasons that PV panels should have an air gap of no less than 100mm from the back of the frame to the roof.


Jip, totally agree, panels are on frames at a good angle on a near flat roof, so very well ventilated. 
There where 2 panels at the time, touched both, the one with diodes fried was extremely hot versus the other one very hot, as you rightfully point out.
Only reason I mentioned this was that once a panel is damaged, it does not necessarily stop as there are up to a total of 72 cells that can still cause havoc if the panel is not covered or removed ASAP.





> If lightning strikes your PV panels, and you have a grid tie system, ...  touching one of the copper water pipes ...


The panels and geysers are quite close to each other, geysers being outside. Would it be an idea to use a earth strap from panel frames to geyser's earth connection?





> A brand new panel


On a good day, days with very high clouds i.e. cloud effect, can result in up to 10% more out of a arrays rated max, my case, even after going on 7 years. So yes, must be very aware of over sizing and using the correct fuse.




> If the panel side is below 50V, ...


My panels are in series, MPPT's are max 150v 35amp. 
600v max for MPPT's for grid tied systems with panels now made for 405w. See that 355w panels today are quite affordable per watt. 
Below 50v is becoming very uncommon. My system is max 150v at 35amps.




> Using an "AC" isolator or circuit breaker is extremely dangerous, ...


Jip, used to be a common "mistake" under solar DIY's as way back the DC ones where very expensive, not anymore. Thank goodness for that.




> Anderson connectors are good, provided they are rated for your installation.


Good!!! 
I prefer a 24v battery bank. The "Anderson" connectors I use are the 50amp ones for the controllers and 175amp ones on the inverter. Can unplug the entire system in seconds. Having paid a lot of school fees being stupid, I decided to do this. Since I went this route, for ME, not a good idea for all, I have "saved" a lot of money see.  :Embarrassment: 


Have  a Victron Multigrid 24v 3000va, CoCT approved using the ESS function from Victron where they quite cleverly balance the system between panels, Eskom and batteries for optimal performance.

48v for me only makes sense in a true off-grid situation or when you want to run your entire house during a failure. In my case the batteries are for a select few dedicated circuits only IF there is a power failure. 

My batts are +-four years old, good for another 4-5 years as I never go below a SOC of 80% (DOD of 20%). Waiting patiently for the lithium banks to mature some more.



So, in conclusion, a electrician can sign off the AC side. Sorted.
The DC side has regulations that "includes certain provisions which are for information and guidance only", so if one follows the exact specifications of the manufactures ito fuses and cable size, using solar cable from a reputable dealer, then all is supposedly fine, but where to get a CoC for that is still not 100% clear on who can give one. Correct?

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## GCE

Hi 

I don't understand the confusion of the COC for PV and DC - It is clearly stipulated in SANS 10142- 1 as previously listed above in the post . A Installation electrician or Master Electrician can issue the COC as long as he has been in general control of the installation.
If a DIY person does it himself then it cannot be signed off - *Only a registered electrical contractor as stipulated under the OHSA can install a PV systems* 
Even the proposal that is on the table at the moment keeps referencing back to SANS 10142-1 even though they now want to call the embedded generation part  _SANS10142-1-1 Part 1-2_ -

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## AndyD

> .........My take on this is an earth strap from the PV panels to the shortest path to a earth via an earth spike. Then join an earth wire from the earth point on the PV panel and take it to the DB earth star point. This way there can be no potential difference between the two points, as invariably all water pipes in the house are connected to this earth, usually at the geyser position. If lightning strikes the roof or panels, it will immediately be directed to earth via the shortest path.
> 
> By joining the two earths, with a minimum of a 6mm square multi strand wire, or preferably a flat strap, then you negate this earth potential difference across the two points......


I'd strongly suggest this should only be done if the supply to the premises is already confirmed to be PME'd on the side of the supply authority. If the supply is not officially PME, ie just TNCS you could end up with very high fault currents through the PV panels on-route to the new earth spike should the supplier neutral be lost somewhere upstream to your premises.

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Justloadit (15-Oct-18)

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## Smiley

> I don't understand the confusion of the COC for PV and DC_SANS10142-1-1 Part 1-2_ -


GCE, my apologies. I came barging in on a Electrician side of the forum. Suspect I am asking the wrong questions or maybe in the wrong thread.

The buck stop at my door the day the fan and proverbial dark matter meets and the professional has left the building, for I am losing trust in what the "professionals" say as the regulations SEEM to not be 100% clear.

AC side I assumed is stock standard, off the shelf home DB setup. Had a qualified electrician, one that has done our entire house in the past, to connect my Multigrid to the house DB. 
*Yet I did not know that:*
- Only a registered electrical contractor as stipulated under the OHSA can install a PV systems. 
- Installation electrician or Master Electrician, never knew there is a difference. Electrician is a electrician sorting ones House DB out.

*The part that is unclear to me*, even with the regs you posted (thank you for your efforts), is *if I do need a CoC for*:
- panels to controllers?
- batteries to inverter?
I.e. the DC side. 

The first time I heard about SANS 10142-1 was from Rubicon mere hours before I made my first posts here. I asked them about what is this new thing about regulations on cables.
Cannot seem to find a copy of that SANS 10142-1 in PDF format, not that it will help. Whom am I to disagree with a electrical professional.


*Ideal answers I was looking for:*
- Like CoCT: Inverter must meet NRS 097-2-1 regulations, what they are, no matter, get one on the list and you are sorted.
- CoC for AC connection to DB board: Your local sparky can do connect that to DB board.
- CoC for panel / batteries, DC side, sparky must have this qualification to give that CoC. Here is  the list of regs he must adhere to ... 


My sincerest apologies if I am wasting your guys time. I just like to understand more, in laymen terms, what I can expect to get for the estimated R10k I am looking at, if I was to believe what I am told.

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## Justloadit

> I'd strongly suggest this should only be done if the supply to the premises is already confirmed to be PME'd on the side of the supply authority. If the supply is not officially PME, ie just TNCS you could end up with very high fault currents through the PV panels on-route to the new earth spike should the supplier neutral be lost somewhere upstream to your premises.


Nice article here giving a good description of PME

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## Smiley

Found a SANS 101421-1:2017 book.

On page 355:
*Type of installation:* DC - the part I am questioning.
*May be installed by:* Electrical Contractor or any person under the control of a Installation Electrician or a Master Installation Electrician.
*Test reports and CoC issuing:* Installation Electrician or Master Installation Electrician, both can install DC and give a Test Report and a CoC.

*Conclusion:*
- Installation Electrician did my DB board, AC side of the install, so that is perfectly legal for him to do.
- I can, if I want, do the DC side and the Installation Electrician can the choose to sign it off, if done under his control.

*Earthing of the panels:* 
- I'll leave that in the Installation Electricians hands after he has done the necessary testing of the system as required by CoCT docs. Too many different professional views.
- Earthing the panels for human safety when there is no AC at all even close to the panels, does not make complete sense.
- Earthing the panels for lightning: I am of the opinion that there is no protection whatsoever against lightning, unless you have a thatch roof and the required protection in place.

I rather unplug the panel cables from the panels, and pray, if I am around. Otherwise it is an insurance claim, if you have that cover.

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## Justloadit

> *Earthing of the panels:* 
> - Earthing the panels for human safety when there is no AC at all even close to the panels, does not make complete sense.
> - Earthing the panels for lightning: I am of the opinion that there is no protection whatsoever against lightning, unless you have a thatch roof and the required protection in place.
> 
> I rather unplug the panel cables from the panels, and pray, if I am around. Otherwise it is an insurance claim, if you have that cover.


By not earthing the PV panels, simply the wind on a hot dry day, will build up static in the frame, and due to the capacitance effect of two conducting materials with a dielectric, which is the aluminium frame, and silicon cells the glass and backing being the dielectric, the cells will charge up and at some point will need to discharge themselves into something, either equipment in which the insulation breaks down, or a human who may touch the equipment.

Anyone who has done ham radio or has placed wire high up to catch the radio waves will have experienced the static generated in the wires to earth, and this is increased when a storm starts building up.

If the panels are not earthed, and lightning strikes the frame, due to the capacitive nature of the PV panel make up, well the energy is going to go somewhere, and what ever is connected to the PV panels will be toast, and if a human is near the vicinity of the equipment, may or may not survive, because the arc is going to jump.

By earthing the panels, the energy will be directed to earth, as this will be the path of least resistance.

The question should rather be
"So are you prepared to take the risk of not earthing?"

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Frans400 (14-Oct-20)

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## Smiley

> ... simply the wind on a hot dry day, will build up static in the frame, ...
> ... because the arc is going to jump ...


Now that makes sense. Thank you! 

If the panels and metal roof can be earthed to the geyser earth, it will not even be a problem.

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## ians

> I rather unplug the panel cables from the panels, and pray, if I am around. Otherwise it is an insurance claim, if you have that cover.


That right there should be your main concern...insurance cover...so long as your insurance company is happy to cover the installation in the event of a strike...fire or death.

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## SilverNodashi

> By not earthing the PV panels, simply the wind on a hot dry day, will build up static in the frame, and due to the capacitance effect of two conducting materials with a dielectric, which is the aluminium frame, and silicon cells the glass and backing being the dielectric, the cells will charge up and at some point will need to discharge themselves into something, either equipment in which the insulation breaks down, or a human who may touch the equipment.
> 
> Anyone who has done ham radio or has placed wire high up to catch the radio waves will have experienced the static generated in the wires to earth, and this is increased when a storm starts building up.
> 
> *If the panels are not earthed, and lightning strikes the frame, due to the capacitive nature of the PV panel make up, well the energy is going to go somewhere, and what ever is connected to the PV panels will be toast, and if a human is near the vicinity of the equipment, may or may not survive, because the arc is going to jump.*
> 
> By earthing the panels, the energy will be directed to earth, as this will be the path of least resistance.
> 
> The question should rather be
> "So are you prepared to take the risk of not earthing?"


It leaves you with quite a tingling feeling and sweating a bit  :Big Grin:

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## Smiley

> It leaves you with quite a tingling feeling and sweating a bit


And so we meet here too. :-)

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## Smiley

So I now have the panels earthed, installed a inverter that is on the CoCT list, have a CoC in hand with the required Engineering report in.

Now CoCT has an issue with the inverter being a hybrid, requiring a suitably acceptable disconnect switch ... grid tie se dinges.

New regs apparently in draft form, hopefully resolving this caveat.

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## griffinn

a single phase tester can issue a coc for a PV sytem provided that the inverter is single phase and he should have some relevant experience. Annexure M is an only  informative guide and not a normative guide hence cannot be enforced in a way that some that an IE or MIE interprets it

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