Cable Size

[Sidewinder]

Ivor D,

How does this test simulate the true impedance of the grid to generated loads @ 50Hz?

A loop impedance test done with say an MFT, does not give you any idea whether the load i.e. the grid is capacitive or inductive, nor does it give you any idea of how this fluctuates with changes in the load either side of the point of measurement.

I understand that it measures (very approximately) the impedance of the supply cables, but that is not the whole story with regard to impedance of the grid does it?

However, I suspect you know that?

I am just curious as to what value you actually give this test and why?

I'm not saying that it is not a valuable test, it is one I do every time I undertake an EFLI test as it is just a 2 button presses on my tester.

Not just in this situation, but all situations.

 

[ivor dispatch]

Explain please, not sure I get your drift...

@ canoe, I am sure you do????,,,,, as if you did'nt you should not be given any advice to Newmen

 

[newman]

Has the installer provided an EIC for the PV install as this will include details of any rcd trip times measured whilst the PV is connected downstream of the RCD?

I have a NAPIT minor works Electrical Certificate, I think it only mentions the RCD in the barn

 

[steptoe]

minor works?

did they not add an additional circuit in for the PV?

or have they took it from another circuit somewhere?

 

[wozz]

A napit minor works cert can be used for the addition of a single circuit unless things have changed.

 

[steptoe]

didnt know that wozz, NIC dont allow that.

 

[wozz]

Napit have a bit more info to fill in on their forms than the nic must be the reason.

 

[wozz]

but can you do a 7671 minor works and add a circuit?

 

[Sidewinder]

wozz,

No you can't.

Well NOT in the eyes of the NIC, and TBH I agree, due to the limitations on the MWC in comparison to the EIC.

IIRC there is a section in the regs that an MWC is not suitable for new circuits.

 

[wozz]

agreed from memory (as i dont use them) a napit MWC has alot more boxes to fill in that a NIC and 7671 form. more like something in between the two. i remember them having printed at the top it could be used for the addition of one circuit. there must be one napit member on here that uses their forms that can confirm or not this.

 

[Zeespark]

Nope, additions only.

AndyGuinness

 

[Sidewinder]

wozz,

I'm not talking about NAPIT certs only 7671/NIC certs.

Not aware of what the NAPIT certs cover, sorry, however, I have been told/seen that they can be used for a single new cct, however, again I don't agree.

 

[newman]

@Newman - As an aside the PV Array on the roof, did you get structural calcs signed off for this for Part A approval (Structural) from the installer(lots dont do it or bother)

No

 

[Sidewinder]

OK, newman, you have had a significant static load added to the roof of your premises, which also can act as a negative wind load, and you have had no proof from the installer that this install meets building regulations with regard to the structural aspect of the install?

That does not sound good to me, when he was there where did he stable his horse & polish his spurs?

 

[wozz]

ok I only mentioned a napit cert as the op said thats what he was given and steptoe assumed they must have used a existing circuit with it being a napit cert that may have not been the case.

 

[professional]

wozz,I'm not talking about NAPIT certs only 7671/NIC certs.

Not aware of what the NAPIT certs cover, sorry, however, I have been told/seen that they can be used for a single new cct, however, again I don't agree.

The NAPIT MW/single circuit certificate contains all of the information that is required for the addition of a single circuit to an existing installation. It was developed specifically for that purpose - so let`s not have any of this NICEIC/NAPIT rubbish.

I don`t USE any NAPIT certs as they are a PITA (with the plethora of boxes) but they do comply with the requirements of BS7671.

So unless anyone is hell bent on digressing to the point of oblivion, perhaps the thread could stay on track?

 

[steptoe]

The NAPIT MW/single circuit certificate contains all of the information that is required for the addition of a single circuit to an existing installation. It was developed specifically for that purpose - so let`s not have any of this NICEIC/NAPIT rubbish.I don`t USE any NAPIT certs as they are a PITA (with the plethora of boxes) but they do comply with the requirements of BS7671.

So unless anyone is hell bent on digressing to the point of oblivion, perhaps the thread could stay on track?

sorry,

I only brought it up as a point where maybe the installer had failed to meet their obligations yet again,

I havent ever saw a MWC that could be used for anything more than an alteration to an existing cert,

I didnt want to start a debate on whos toilet paper was better.

 

[professional]

Unusually, NAPIT do a combined MW / Single circuit certificate which (I suppose) some people may find useful. I don`t use any NAPIT certs because I think thay are total **** but that`s just my oppinion. Some may well like and use them.

 

[ProDave]

This thread just seems to keep going round and round.

The DNO has done some tests and given a very unhelpful ambiguous "it's all okay" answer with no real facts.

The orignal installer refuses to accept there is anything wrong.

I really think, as I have suggested before, it is time for you to employ your own decent electrician, one that knows something about Solar PV and the regs involved, to come and do a thorough analysis of what's wrong and exactly where the excess voltage is occurring.

Then, when you have a properly written statement of what's wrong, borne out with some facts and figures, and with those facts and figures related to the relevant regs. Then you might be in a position to give that report to the original installer and tell them to fix it.

Unless you do that, I think you will still be getting pushed around forever.

 

[Sidewinder]

Nope i genuinely didnt understand your words / comments / phrasingI can give advice quite freely to be honest

First one Dont eat Yellow Snow

@SW - Thanks

Do I need to apologise mate?

Sorry just in case.