Lights trip after a few minutes

[leemag]

Hi All,

I'm looking for some advice. I've added some downlights to a downstairs room and they all seemed to work okay, however, as a test I turned all the downstairs lights on and after a few minutes the fuse trips.

We have quite a few lights downstairs and I wondered if it was just a case of there being too many for the fuse or if it is something else. What is throwing me is that they don't trip immediately.

Any advise would be brilliant.

Thanks

Lee

 

[TicklyT]

How many lights?
What is the rating (Watts) of each light?
What is the rating (Amps) of the breaker?

 

[Chri5]

Maths............

6a MCB / fuse for a light circuit will allow 6 x 230v or 1380w of load.

1380w of load might not trip since most MCB's and fuses have a + % tolerance.

As mentioned check all your bulbs and confirm back the total watt load.

I would add that if you have standard lamps in other areas of the circuit, changing from a few 100w bulbs down to 21w low energy could help reduce the total load of the circuit.

Have the lights been wired as new or have you simply added them on to existing, aged wiring?

 

[leemag]

Maths............

6a MCB / fuse for a light circuit will allow 6 x 230v or 1380w of load.

1380w of load might not trip since most MCB's and fuses have a + % tolerance.

As mentioned check all your bulbs and confirm back the total watt load.

I would add that if you have standard lamps in other areas of the circuit, changing from a few 100w bulbs down to 21w low energy could help reduce the total load of the circuit.

Have the lights been wired as new or have you simply added them on to existing, aged wiring?

Hi Chri5,

Thanks for the speedy response. I've counted up and we are way over the total allowed wattage. I'm going to change the bulbs for lower wattage ones.

However, I have spare fuses on my fuse box and wondered if you knew if it was possible to split the circuit over two fuses. I'd definitely get a professional to do it but wondered if it was a) possible and b) a big job.

Thanks

Lee

 

[Chri5]

It's quite possible to split the load, equally subject to the wirng condition and cable size (likely to be either 1.0mm or 1.5mm ) that the circuit fuse could be increased to 10A (if it's a 6A and the moment).

Best to have a pro in and get them to check the wiring and confirm whch of the methods is best for the site conditions.

If it's a fuse change, then it's a simple (less than half a day) job to test the wiring and update the MCB.

If its a split the circuit and run in a new feeder fro the fuse board that's going to be longer.

Since I have no knowledge of the site, the age of build, fixed flooring, access for cables- please accept the time suggestions as 'vague'.

Please report back post actions.

 

[leemag]

It's quite possible to split the load, equally subject to the wirng condition and cable size (likely to be either 1.0mm or 1.5mm ) that the circuit fuse could be increased to 10A (if it's a 6A and the moment).

Best to have a pro in and get them to check the wiring and confirm whch of the methods is best for the site conditions.

If it's a fuse change, then it's a simple (less than half a day) job to test the wiring and update the MCB.

If its a split the circuit and run in a new feeder fro the fuse board that's going to be longer.

Since I have no knowledge of the site, the age of build, fixed flooring, access for cables- please accept the time suggestions as 'vague'.

Please report back post actions.

Thanks Chri5. I'll get someone in and let you know what happens.

Lee