Replace rcd?

You are carrying out alterations which I presume entails additional socket outlets. These outlets will require additional RCD protection which you have. You must now question whether the type AC device is suitable for additional protection in accordance with current requirements, your installation must adhere to current requirements. I would suggest to you it is not.

 

Some good comments have been made, the big one is we have used rectifiers or diodes on the mains supply for more years than I can remember, now 72, the likes of the three port valve have been around for a long time, and I note my inverter for my solar array stated one can use a type AC RCD.

What worries me is a combination of faults, with 14 RCBO's the likely hood of a DC current stopping a RCD working when a second fault arrives is slim, and type A is only rated at 6 mA and even some of the type B's can't handle pure DC, and 6 mA is so small that unless one has so detector to auto disconnect the supply when DC is detected, it does seem rather pointless to change, would no longer fit type AC, but to change when the RCD is only a secondary protection to start with, seems to be going OTT.

It is a watch my back exercise, it is not are they needed, it is if some thing goes wrong can they blame me. Clearly with a TT installation where the RCD is primary protection one has to look at it in a different light, so likely I would change with a TT installation.

With a TN, it is not so cut and dried, so in the main you can't get a single modular width RCBO type B, although all the boxes my type AC came in were marked type B, I would assume curve B? But to fit a type B I would need to return to one RCD protecting many circuits, so it comes down to a risk assessment.

My old house it does not even show what type are fitted, sure there is a BS number some where on them, but I don't have a list of which are type AC, A, F or B so no way of knowing, so if the RCD tester trips the RCD and you have not adding some thing which stipulates what type is required, then unless TT I would leave it.

I would change one of these but as to ELCB-c if 30 mA that's good enough. Was the ELCB-v shown susceptible to DC freezing? Should we move back to them?

 

This thread has got me thinking.
Think I shall make a flowchart that will explain to the poor customers, no matter why the invited the electrician into their home, they need a new board.

 

It is going to be a common problem much like the increased use of RCDs through Regulation changes.

 

Always carry a selection of boards with me and insist on changing the existing board, when invited to friends and relatives for tea, of course I let them boil the kettle first.
When they ask why I tell them the 18th says you shall boiler the kettle before board change.

 

Or even Matron:

 

On an EICR, it is a C3. Not only according to me, but also Best Practice Guide 4, issue 6.

However, if installing new equipment all the work must be to current regulations. Meaning Type A in most cases.

 

Right answer, wrong question.

 

I go one better, I carry pictures on assorted CU's and accessories with me pinned inside a big raincoat when I take my dog to the dog park, anyone walking near to me and I whip open the coat and say 'fancy something new today'

It works, I have got a load of new customers and what's more handy is they all work in the same constabulary cutting down travel time.

 

Yes, I was having (another) senior moment.