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What are the 'rules' regarding where this switch has to be located?

eg Can it be eg. in the attic with the inverter or must it be 'next to' the main consumer unit? If it were close to the consumer unit but the other side of the wall eg in the hall instead of the kitchen (where consumer unit is) is that OK? ie does it have to be visible from the consumer unit?Any other limitations?

Any ideas? Thanks for looking.
 
You need an AC isolator at an accessible point, so that means where you can easily get to it.
If the inverter is in the loft, then you should have one there also.

I hope this helps
 
Do we agreed that a double pole RCBO at the consumer unit is classed as a isolation point (and can be locked off) ? Never done it without a rotary isolator but just wondered what the general opinion was.
 
old guidance was a bit ambiguous, new draft guidance clarifies it as yes, providing it's clearly labelled.

An a.c. switch or combination of switches must be provided for isolation and maintenance in the installation.


A switch for mechanical maintenance shall be provided in close proximity to the Inverter and shall fulfil the following conditions:
 switch all live and neutral conductors
 be securable in the OFF position only
 clearly show the ON and OFF positions and be labelled as ‘PV system – main a.c. isolator’


An accessible means of isolation shall be provided to isolate the a.c. circuit.
MCB’s, RCD’s and main switches installed in accordance with BS7671 and in an accessible location can be used to fulfil the requirements for an accessible means of isolation.
 
Thanks Gavin,
Doesn't it make you laught they say 'switch all live and neutral conductors' Isn't neutral a live conductor as per 17th edition?
Guess this really does save us from the additional cost of an ugly rotary isolator at the consumer unit then.
 
my understanding, and my assessor confirmed this, is that under the current regs the isolator must be lockable by a generally available lock, I.E. a padlock, therefore a rotary isolator must be used.
They're cheap enough I don't really understand why you wouldn't?
 
my understanding, and my assessor confirmed this, is that under the current regs the isolator must be lockable by a generally available lock, I.E. a padlock, therefore a rotary isolator must be used.
They're cheap enough I don't really understand why you wouldn't?

True enough, until they need fitting in hallways - they look awful.
 
The Doepke MCBs, RCDs and RCBOs we provide have their own proprietary lock-off clips, which can then be secured with a padlock if required. Santon do a nice flush or surface mount stand-alone AC isolator (lockable in off position only, of course) as part of their new DSS range of products.
 
When mine was installed, the installer agreed with me there was no room for the bulky rotary switch anywhere near my consumer unit, so the one and only is by the inverter. Since this is in my airing cupboard, it's accessible, but it's excessively bulky and is in the way. It is a 3-phase plus neutral industrial affair (4-pole) rated at 33A per pole. Massive overkill for my 1.4kWp system!!! It's about time manufacturers made switch spur units for domestic use that incorporated the required locking mechanism - a flap like a padlock hasp over the rocker switch that automatically switched it off when shut should suffice.

As for the CU - the best I could do was to put a label on it saying where the AC isolator is.
 
my understanding, and my assessor confirmed this, is that under the current regs the isolator must be lockable by a generally available lock, I.E. a padlock, therefore a rotary isolator must be used.
They're cheap enough I don't really understand why you wouldn't?
it's not really a matter of money. We're installing a tails block and garage unit for each system anyway, which uses a dual pole RCD + MCB, and IMO it's better / safer to use this as the dual pole cut out at that end of the AC cable, then use a seperate rotary isolator at the inverter.

what's so special about a solar PV circuit that it can't use the same method of isolation as ever other circuit in the house?

To me, the fact that the draft revision of the guide specifically says this is ok is sufficient evidence that the logical conclusion we'd already reached is correct, and had we not had several mad rush periods in the industry that guidance would have been published as current by now anyway... it is after all guidance, not regulations. But I think we've had this discussion before.
 
I've got to agree with you Gavin, but regs is regs and we have to work to those in place at the time.
Why isn't a 20amp isloator satisfactory, it is for everything else!
Why, on a smaller system, couldn't you use a fused spur, then you could just take the fuse out!
lets face it, there's an awful lot in the guidence/regs that really doesn't stand up to scrutiny
 
yes, but, it's the standard you are expected to work to, so, although not a statutory instrument in itself, to perform your legal duty of care and to satisfy the vagaries of consumer law, building regs, wiring regs etc etc you would need to be able to show you followed the guidence, or demonstrate very sound reasoning as to why you didn't.
Our contracts also state that the system will be installed in accordance with the regs, statutory requirements and guidence, so failing to do so would render us in breach of contract. It's the customers reassurance that things will be done properly.
like the highway code, IT may not be law, but not following it may mean you fall foul of the law
 

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