Bit of an odd one...

[Johnnym]

Hello all !

Wonder if any one can shed light on this one ?

After a living room light blew a fuse it now wont light up a regular bulb at all but will light up a energy saving bulb with a flickering light .

Fitted a new light fitting but still the same prob !



.

 

[echoes]

Did it blow an actual fuse (as opposed to an MCB or an RCD)?
Have you looked at the wiring in the switch(es) for signs of problems?
Can you use a multimeter?

 

[ban-all-sheds]

What do you mean by "a living room light blew a fuse"?

The symptoms you describe are probably caused by a loose connection making a high-resistance joint, thus dropping the voltage too low for a normal lamp to work but high enough for a CFL to slowly charge up, strike and go out, repeat...

It's a fire risk - you need to find it as a matter of urgency.

Are all the other lights on the circuit OK?

Has any work been done which could have damaged a cable?

have you thought to check the connections in the light fitting or the switch?

 

[Johnnym]

Did it blow an actual fuse (as opposed to an MCB or an RCD)?
Have you looked at the wiring in the switch(es) for signs of problems?
Can you use a multimeter?

Sorry...should have posted more info.Many thanks for reply.

It blew a MCB and i recently fitted a dimmer switch to said light.Will have a nosy at that one.

i cant use a multimeter but id imagine its not beyond my bounds.

 

[echoes]

Is that CFL dimmable? Most are not, and will flicker.

Have you tried it with a normal tungsten or halogen bulb?

 

[ricicle]

The dimmer was probably fried when the lamp blew. There is possibly just enough current through the dimmer to momentarily strike a CFL but not a filament lamp. New dimmer required and fit lamps that have built in fuses.

 

[Johnnym]

Just put a normal switch in and all is well.Prob made an ar#e of puttin the dimmer in.

Many ,many thanks for all replies !

.

 

[ban-all-sheds]

It's more likely that when the lamp failed the current surge damaged the dimmer.

Think - the surge was enough to trip the MCB, and the dimmer is only rated at 1 or 2A.

As ricicle says, better lamps with built-in fuses are a good idea, but they don't always do the trick. Good quality dimmers are also important.

 

[timbim]

Think - the surge was enough to trip the MCB, and the dimmer is only rated at 1 or 2A.

Yet they are allowed to be protected by a 6A MCB. Is there not something of a conflict there?

 

[ban-all-sheds]

No - the MCB is to protect the cable, that's all.

 

[timbim]

No - the MCB is to protect the cable, that's all.

So should the dimmer not be fused itself? Otherwise it can happily have 5A flowing through it indefinitely, at best breaking it and at worst starting a fire.

 

[ban-all-sheds]

So should the dimmer not be fused itself?

Many are, but often the fuse is not replaceable, so when it goes the dimmer is just as useless as if it got wrecked. I guess the idea is that it prevents a hazard.

Otherwise it can happily have 5A flowing through it indefinitely, at best breaking it and at worst starting a fire.

Actually it could be 6.78A indefinitely, or 8.7A for up to an hour.

Like any other electrical component it's up to the user to not overload it.