RCD for electric blanket

The wife's underblanket is designed to be used all night if required. It must be now 15yrs old. I regularly visually check it and there is no fraying or sign of deterioration but I'm wondering if it would be wise in any even to plug in via an RCD adapter.

Thoughts?

Just keep paying the life insurance?!

In article , AnthonyL writes

Can't do any harm but be aware that the adaptor type products are IME more prone to false trips when left on for extended periods (weeks/months) than ones designed for consumer unit use so a trip may not necessarily indicate a fault in the blanket.

You don't say if the circuit it's plugged into is already RCD protected. If it is, you won't really gain anything and there probebly wont even be any discrimination, ie the CU RCD will trip as well.

Why not?

However teh RCD is unlikely to help if the thing wants to catch fire (assuming it is a Class II appliance)

If it's 15 years old I'd change it anyway: I have just done exactly that myself, being a big, B-I-I-G fan of electric blankets (as I've said in another thread recently, my wife gets way too hot, so I just have a single, on my side of the bed).

I got this one:

I'm extremely pleased with it -- it's far in advance of my old one, though I doubt if it will last as long as that (about 15 years in my case, too). Greatest thing for me is: heats up to red hot in 5 mins.

hth John

BLOODY HELL!! I've just noticed that that item is FIFTEEN POUNDS less than I paid, in the store, one month ago!!!! Maybe they've reduced them because we're coming out of winter?

John

Well I'm not sure if I've got an RCD. I've taken photos of a breaker that sits between the meter (wires into top) and the main fuse box (wires out the bottom). Had to mess around with a mirror to get the circuit diagram but I can't see any description, make etc.

Is there a reasonably safe way to check if it is an RCD (short live to earth on a 3 pin?)

I'm the opposite - my wife is always cold (well not for about a dozen days in the summer).

Looks promising - thanks for the heads up.

It looks like an ELCB, the precedecessor of the RCD

That's an ELCB, which won't offer any shock protection. I'd always use an RCD with an electric blanket. They kill more people than all other domestic appliances combined

NT

That looks like an old voltage operated ELCB (earth leakage circuit breaker), we used to have one like it. Used in our house anyway to give whole house protection in the event of a voltage flowing to earth (TT earthing)

Not that ours ever tripped. even when by B-I-L got a shock due to a live/earth fault.

AIUI Doesn't really give the protection of an RCD to individual devices or circuits

(ours since replaced with a time delayed RCD

Oh - I thought that if the blanket shorted through a person that should trigger it :(

I presume it isn't a big job to replace it? But why a "time delayed"?

I'll buy an individual RCD anyway just to be safe, and probably a new blanket.

You can fry in hell & an ELCB won't give a damn. RCDs care 50% of the time, when its a L-N fryup they don't either.

No. So as you add RCDs further downline, those trip instead of the whole house going off.

NT

No, it protects against a fire if your earth connection is not good enough to make a fuse blow. It is not intended to protect against electrocution.

If it's not nuisance tripping and still works when you press the test button, I would leave it there, as simply replacing it with an RCD no longer meets current regs either.

To meet current regs, you would need to replace the CU with a 17th Edition CU, or replace MCBs with RCBOs in a CU which doesn't have RCDs. (Then the ELCB could be removed.)

Replacing ELCB with RCD would give some added shock protection, even if not now compliant. It might also introduce false trip problems. Keeping the ELCB and adding RCD cover in the fusebox/CU would be better, but its more work & money. Neither is obligatory in most situations.

NT

I bought an RCD, put an open plug on it and shorted live to earth. Nice big bang, both RCD and ELCB (or whatever it is) tripped and everything in the house went dark.

So am I right to think that I'm getting all the protection I need from the ELCB?

Somewhat confused!

No. You created a huge fault current, probably over 1000A. Try creating a 30mA current - the RCD should trip, but a delayed RCD or ELCB won't.

NT

Thinking about it further I don't think the RCD triggered, it merely reset on having the power cut?

Still confused.