Plug-in Solar supposedly going to be 'easier'?

Humm. We did have something similar some years ago with micro wind turbines (which eventually died a death as turbine efficiency at that size is so awful they'd never repay their embedded energy).

On the other hand, things might not be quite as bad as they first appear. Once unplugged the inverter would presumably loose all earth reference, so while the L & N pins might still be live w.r.t. to each other, they'd be separated from Earth - so like a bathroom shaver socket - there'd be little risk of a conventional shock to Earth. Even a finger-to-finger shock is unlikely to be lethal if all the finders are on the same hand (it certainly hurts, I can vouch for that, but without a path across the chest the chances of ventricular fibrillation seem small.) Touching both pins with opposite hands, in order to get a shock across the chest, seems much less likely, especially if it needs to be done within the short time after unplugging it takes a modern inverter to spot the loss of mains and shutdown. Older inverters can be pretty poor on that count (my old G83 one takes several seconds) but if more modern ones could achieve that within say 1 full cycle (20ms) that would seem at least comparable to additional protection offered by 30mA RCDs.

Potential loss of overload protection of the host socket circuit might need some thought (but if the power of the panel is "small" the additional risk would also seem small - after all how often does a ring run within a few hundred watts of the MCB tripping? How often have you seen a domestic ring overload protection operate anyway?)

RCD directionality might also be a consideration (but there are likely hundreds of thousands if not millions of early PV installations wired on the load side of conventional RCDs with no noticeable piles of bodies in the streets).

   - Andy.

BS 7671 does not concern itself with product standards for equipment that may be plugged in to socket outlets.

If the government ae so keen on these devices no doubt they will commission a product standard for devices being placed on the UK market that protects the public, livestock and property.

I do not believe that currently there is a product standard for these devices?

JP

There are existing standards for time to detect loss of mains, and limit output voltages and currents that are for micro inverters that might as well apply as they are.

Generally the govt does not 'commision a standard' rather manufacturers decide the generic standard is too hard for their type of product, and try and push through a dedicated one that is suitably shaped.

Mike.

There are existing standards for time to detect loss of mains, and limit output voltages and currents that are for micro inverters that might as well apply as they are.

Generally the govt does not 'commision a standard' rather manufacturers decide the generic standard is too hard for their type of product, and try and push through a dedicated one that is suitably shaped.

Mike.

I think the government would ask the BSI to come up with a standard for these plug in devices. The usual practice is for the BSI to ask for input from industry interests and professional bodies to draft a standard for public consultation. The BSI recovering their cost from sales of the standard.

I am not aware of a current IEC, HD or BS(EN) for plug in microinverters?

As for AJ comment about not seeing bodies piled up in the streets, what is the required number of deaths or serious injuries before a standard needs to be produced?

I have been involved with clients in respect of PV installations who have been the source of fires. I quick search of the internet will reveal how common they are.

I have produced an evaluation form listing all the relevant standards for PV inverter selection. It is freely available to anyone who would like a copy by emailing me on info(the word for at)astutetechnicalservices.co.uk. I have sent more than a hundred copies out already on LinkedIn. 

JP