Gavalnic Isolation and bonding to array

[shes-electric]

BTw I do realise this is Galvanic not the miss-spelled mess of a word I have used.!

Hello,

can anyone tell me their thoughts on the inverters that have 'galvanic Isolation' rather than transformers? I have used SMA Inverters before that had this built in and when I spoke to SMA technical team they insisted that these inverters only need to be on an MCB and not even on an RCD because of nuisance tripping. Is this a pile of :****:because I feel unsure as obviously this is not providing basic and fault protection. SMA insist that as the DC current can not be passed through the AC circuits its fine.

The DTI guidelines obviously only distinguish between those with transformers and those without. It is apparent that any inverter without a transformer should mean that the PV array is bonded. Any suggestions about best practice?

 

[Graeme Harrold]

With regards to SMA TL inverters, bond the array and if necessary fit a 100mA RCD as per the instructions only if needed. RCD is NOT basic protection, its additional due to cable routing.

 

[shes-electric]

Can I also Make clear tat I understand 'Galvanic Isolation' is a fancy word for transformer but the Inverter manufacturers appear to be using 3 terms. Transformer, Tranformer-less and those with galvanic isolation which is why i am asking the question.

 

[Sparky Ninja]

What do you mean by it not providing basic and fault protection?

 

[shes-electric]

What do you mean by it not providing basic and fault protection?

Sorry what I meant to say is that RCD's should not be the only means of basic and fault protection. There seems to be a lot of differing opinions on earthing arrays amongst installers and I wanted to get a definitive answer.

 

[Graeme Harrold]

For now, follow the guidance given in the Dti Booklet