British General 13A RCD Fused Spur White (8250P): Puzzle

[Maurice]

One of these was fitted 5 years ago to control the ceiling light fitting in the utility room; fitted with a 3A fuse, but can find no instruction leaflet, and have failed to deduce the use of the buttons. (Is mounted high on inner garage wall, so difficult to access)

Question: (1) How does one use the buttons on this RCD to test, and reset? (1 orange, 1 red)

(2) There seems to be no on/off function. (Use red to disconnect?)

(3) How does one get the fuse out to check it? Seems to sit in a somewhat fragile cradle.)

[Maurice]

See:

[Adrian Caspersz]

The screwfix site show the GB model number as 955RCD

Maybe this is similar ..

[John Rumm]

Manual:

[Robin]

see

[Chris Green]

I don't know about 1 and 2 but the answer to 3 is usually with a small screwdriver and a lot of swearing.

[Maurice]

I know what you mean! The problem is that the unit is so high on the wall that I can't readily see what I'm doing.

When I levered the fuse cradle out, I could still not remove the fuse to check it, so I pulled the cradle all the way out. (Too late did I eventually see in the Data Sheet that it is not meant to be pulled completely out...)

Fuse OK (If so why wouldn't the new bulb (28W CFL Square 4-pin 2050lm GR10q) still not work after pressing Test & Reset?)

New problem now is that when trying to replace the fuse & cradle back into the slot, the fragile cradle snapped in two, so I now have a u/s RCD...

So need to: (1) Take new bulb back to local shop to check still works.

(2) See if possible to buy new cradle and get it & fuse back into unit. (If not posible, would be cheaper to buy new RCD and take out its fuse cradle, rather than call electrican out to replace whole unit.) Problem with these 4-pin 'compact fluorescents' is it makes it difficult to check that its socket is 'live'...

[Mike Clarke]

And run the risk of doing exactly the same damage to the new fuse carrier again. Many of these plasticy bits are designed to snap in once and not come out again without being destroyed - unless the whole unit is dismantled.

[Maurice]

My thought also.

Well, I've just taken another look. The unit has a front panel, which appears to be mounted onto the rear base that contains the cabling connection. The fuse-holder seems to be within the front panel, so I'm conjecturing that if the front panel was taken off and replaced by the equivalent front panel of a new identical unit, then that could restore the status quo without having to mess with cable connections.

But I wouldn't want to try that without discovering how to cut off power to the unit first. [The cable down into it just disappears up into the roof space. I suspect it then descends into an adjacent box that has a white wooden lid screwed down on it, possibly containing the rest of the connections for the power sockets in the utitity room. But I still don't know where the power to that is controlled from.]

Suspect no choice but get the electrician back in..

Regards,

[Mike Clarke]

That sounds like dismantling the unit. I wouldn't like to predict how many springy bits will fly out when you do that.

Unless you're absolutely sure what you're doing then the only safe thing is to replace the entire unit.

Well turning off the main switch on your consumer unit should turn off power to everything in the house. If for some reason there's more than one consumer unit then turn them all off

[Maurice]

Agreed! Regards,

[Dave Plowman (News)]

Can I ask why you have an RCD - rather than just a switched FCU - feeding a light?

[Maurice]

Well, the unit has a base plate, into which the cables are affixed, and a front plate that fixes onto the baseplate - rather like our CH programmer, whose display failed (in the top plate) and I was able to replace that top plate from a replacement programmer unit, without touching the wiring in the base plate.

Have now found the contact breaker in the main unit that has the 'utility room' label faintly inscribed as a label. So can isolate the spur RCD.

The mystery is that neither contact breaker (up) nor 3A fuse in spur RCD were 'off', so why did the replacement light not come on? I had been assuming one or other must have been off'ed by the old bulb failing.

WIll try to get new bulb checked out at shop tomorrow.

[Maurice]

Because the electrician who installed the utility room electrics believed even lighting units that are in a room containing water need the protection to be provided.

Regards,

[Maurice]

Sadly, not so, I find. Main unit just fixes onto shell wall baseplate. Would need to disconnect faulty unit, remove it and connect new unit to old wires. I now know exactly how to do that, but will have to get an electrician to do it, as at my age (85) I dare not risk the danger of overbalancing when reaching up towards unit high on garage wall for the time that would take.

Many thanks for all responses. Much appreciated...

[ARW]

Then your electrician is a dick.

Swap the RCD unit for a bog standard unswitched fuse spur.