DC isolators......lockable?

[Steve_rutland]

Just a quickie, in order to meet regs, do DC isolators need to be lockable on a pv install?

 

[JulianC]

Nope. No specific requirement for lockable DC isolators in the 2nd ed. DTI guide.

 

[Steve_rutland]

Nice one, cheers for that

 

[Steve_rutland]

Righty, got an installer here saying my DC isolators have to be lockable. Will try and find the reg he is quoting.

 

[Steve_rutland]

KG32 T104
This is the reg he is quoting. Any ideas?

 

[JulianC]

Reg? You won't find it. There isn't one. Don't even need a separate DC isolator nowadays, if the inverter has one built in that meets certain criteria, none of which involve the word 'lockable' ;-)


KG32 T104 is the model number for a Kraus & Naimer DC isolator


<edit> might be a good time to find an alternative installer. Y'know, one that knows what the hell he is doing.

 

[Steve_rutland]

I've read a lot of posts that agree with what your saying and I think you're right, but, he's emailed me a link to a page on Swithenbanks lockable DC isolator that states it has to be lockable. Sooooo confused lol

 

[Steve_rutland]

25A DC Isolator Lockable at Swithenbanks Alternative Energy | Grid Tie Inverters | Solar Photovoltaic
This is what I was sent.

 

[whinmoor]

I don't believe the DC isolators need to be lockable whereas the AC must be.

 

[Steve_rutland]

Lol, well I've got 4 here that aren't lockable, but this one guy is quoting this reg and website that says they need to be, so now I'm scratching my head Doh!

 

[JulianC]

I've read a lot of posts that agree with what your saying and I think you're right, but, he's emailed me a link to a page on Swithenbanks lockable DC isolator that states it has to be lockable. Sooooo confused lol

So what? Ask him to email you the relevant reg. or the passage from the DTI guide/G83 document that says it must be lockable. He's not quoted any reg at you, just shown you a link to a retailers website. Last time I checked, information provided on retailer's websites was not legally enforceable. Alternatively, buy new isolators. Why ask the question?

 

[SibertSolar]

Maybe he's getting confused about the requirement for an AC isolator that is securable in the office position only? The reason I say that is that the K&N unit is actually an AC isolator that, according to K&N, is load-break rated for DC and passes the requirements for DC21 utilisation category......(little bit tongue in cheek but those who know me will know why....) ;-)

 

[SibertSolar]

bottom line - DC switch disconnectors or isolators do not need to be securable in the office position, according to the "best practise" recommendations, although it certainly wouldn't hurt if they were. Also, as has been stated already, if your inverter has a suitably rated unit already built-in then you do not necessarily need to fit an additional external DC switch disconnector near to the inverter. Whether you choose to fit one near the array or not is up to you.

 

[ian.settle1]

I dont do PV systems but I would prefer to have a DC lockable isolator as the last thing I would want is some twonk to switch it on whilst I was working on the invertor or AC end.

But then again that is my opinion.

 

[Steve_rutland]

The inverters unfortunately don't have built in isolators and I have 2 top notch ABB double enclosed units here which aren't lockable but were pricey. Hence my concern. He's asking now for my inverter MCS compliance data New one one me, as I thought that was covered by the G83/1 compliance report. Think you are right about the AC ~ DC isolator confusion. Just don't know what this KG32 T014 thing is all about.
:-/