Array bonding needed?

[Gavin A]

well if that's the problem they're trying to solve, I'm not too concerned as I'd expect that sort of a fault to trip the RCD on the AC side 99.9% of the time, and we've been installing an individual RCD on each AC circuit on virtually every install we've done.

it'd also require multiple fairlures within the inverter, and the inverter remaining stuck on the on position - something I can't see happening for anything other than a lightening strike.

It's also solved by instructions to switch the ac and DC isolators off before going on the roof.

 

[moggy1968]

Hmmn
thats a covulted set of circumstances bearing in mind the regs require protection against single fault conditions

 

[steve Leese]

http://www.greenhippohut.com/sites/default/files/capacitive-discharge-currents.pdf Has this any bearing on what you are discusing, as reguarding the earthing of the array.

 

[yellowvanman]

Spoke to someone who is influencial in the MCS arena and in conversation asked him about bonding of the array for TL inverters and he told me to read the new version of GN7. Yet to read it but lead to believe it states no need to bond.

He also when onto to say the DTI guide is 'guidance' only and then started on about lockable ac isolators, dc isolators when you've got integral isolators in the inverter and type A RCDs!

Apparently the new DTI guide will reveal all!

 

[rich.250]

Spoke to someone who is influencial in the MCS arena and in conversation asked him about bonding of the array for TL inverters and he told me to read the new version of GN7. Yet to read it but lead to believe it states no need to bond.

He also when onto to say the DTI guide is 'guidance' only and then started on about lockable ac isolators, dc isolators when you've got integral isolators in the inverter and type A RCDs!

My point exactly. These publications are only guides. BS7671 holds all the answers for the requirements.
I don't see the need to bond them. Unless maybe they require a functional earth. This is earthing not bonding anyhow.
This would be to the MET and never to an electrode.
All the confusion seems to be caused by people listening and trusting too much to what there told and not checking for themselves.
Good to see everyone on here is trying to get this confusion sorted

 

[TedM]

It's mandatory to comply with all the double-ticked items in the DTI Guide in order to comply with MCS rules - or are MCS now saying that they can bend their own rules? Also the single-ticked items are mandatory unless you can show good reason for a variation.

This is all in MIS 3002 v2.1 para 4.2.

For the purposes of this standard, all double-ticked items in the DTI guide are mandatory. Compliance with all single ticked items is also expected unless reasonable justification can be given.

But having said that there are no ticks, single or double, against the tree diagram itself.

 

[babba]

Well Ted you just set this thread off AGAIN...I hope you can sleep tonight...

 

[Gavin A]

But having said that there are no ticks, single or double, against the tree diagram itself.

well if there's no ticks then there's no ticks.


also, if NAPIT send a sodding gas engineer out to assess us again, and try to get me to bond the frame to the MET on an SB1200 inverter with full galvonic isolation just because it's near a skylight.......:66: