What amp fuse do I need for my light curcuit

[dadlington]

Over the past month or so, 3 lights in my house have blown, and have blown the fuse in the fuse box in my garage. Each time, I have replaced it with a 5 amp fuse, only for it to blow again the next time a bulb pops.
I am wondering whether a 5 amp fuse is too low and whether I should try a 13 amp one, or whether the 5amp is correct and I need to get an electrician in to chek out my wiring.
(I am hoping that this isn't the case, as I have heard that this is expensive).

[chrisrob]

It is extremely unlikely your lights will need more than a 5 amp fuse. A 5 amp fuse will let use 1000W which would be an extremely bright bulb - a stage spotlight perhaps?
DO NOT use a 13 amp fuse. It's likely the lighting circuit will not take it and whatever is causing the short circuit could start a fire.
There is most probably another reason for the short circuit. Call in an electrician to investigate.

[Hymie]

Normally a household fuse-box will have two fused lighting circuits (fused at 5A), one for the downstairs ring and one for the upstairs. This allows for a total lighting load on each ring of just over 1,000W. Given than a 100W bulb if sufficient for most rooms, 5A gives ample capacity in most applications.

When a bulb blows, often the filament within the bulb breaks and causes short circuit across the bulb element. Within the design of the bulb is a deliberate weak link (fuse), which should break when this happens (saving the 5A circuit fuse from operating).
You might just be unlucky that this weak link within the bulbs� has no operated as designed, but the 5A fuse box fuse is doing its job � protecting the circuit from an excessive current, due to a fault.

Many modern house installations use over-current trips instead of fuses. These tend to be more sensitive to this problem, resulting in the loss of the lighting circuit when a bulb blows � but they only need reset the trip, rather than replace a fuse.

As other have said, you should not increase the amperage of the fuse without having an electrician check out the wiring to be adequate.

[raysparx1]

If the fuse is "Blowing" it is not overloaded, so as has been said on no account put bigger fuse in, if it was overloading and you had fuse wire it would melt, if you have circuit breakers they will trip, so you just re-set them, probably just coincidence, but if it keeps happening call in a sparky and get it checked, good luck, Ray

[Brooksy]

I`ve found over the last 10 years that the modern, switched circuit breaker type of "fuse box" is very sensitive to bulbs blowing if the broken element shorts as it blows. The old type of fuse very occasionally blew. As others have stated above, going above 5 amps is dangerous.

[Disco Fever]

Have your old type fuses changed for a circuit breaker board so when the lamp blows the miniture circuit breaker trips out and all you have to do is trip it back in again, thus you dont have to keep buying fuses....


Chrisrob a 5 amp fuse will give you 1150 watts as 1000 watts would be 4.35 amps: 1000/230.

Yes you divide the watts by 230 volts not 240 as the EU has got the UK to drop the voltage to 230 volts....