Exterior Lighting keeps tripping

[steve_warman]

Hi,

I have 2 exterior wall mounted lights running from one fused switch.
The paperwork said to change the fuse to a 13a if there are more than 1 light in the chain so that was done.
For some reason when the lights are on the main breaker keeps tripping sending the house into darkness.
My first course of action will be to change the fused switch to a trip switch to try and stop the rest of the house going dark.
Can anyone suggest a way to track down why it keeps tripping?

The lights are 150w halogen lights with a pir on each.

Thanks

 

[JohnD]

I suspect you mean the RCD is tripping (not the MCB) but you do not say so.

Two 150w lamps should be fused at 3Amps (or 5 would do) NOT 13Amps!!!

Please say what the thing is that is tripping.

Have the lamps ever worked since they were fitted?

 

[steve_warman]

I don't have a consumer unit, just a series of breakers.
The lamps work for a period of time from 30 seconds to all night but when they trip it brings down all electrics.
The lamps were fitted before we moved into the house but were 500w lamps and quite old so they were replaced. They tripped before being changed as well.

 

[JohnD]

I suspect you mean the RCD is tripping (not the MCB) but you do not say so.

Please say what the thing is that is tripping.

This is an MCB

and

This is an RCD. Note that it is twice as wide and has a "Test" button on it.

This is a main switch which is the same size as the RCD

This is a Consumer Unit which is an enclosure that the main switch, MCBs and RCD go into.

and here is an older Consumer unit of a very common style

 

[steve_warman]

OK, I have an old style consumer unit for the lighting and interior circuits and a single standalone switch which looks like the switch part of the old style consumer unit, this is separated from the fuses in the consumer unit

 

[JohnD]

And what is the thing that is tripping?

 

[steve_warman]

The main switch

 

[JohnD]

OK. Have a look at it, see what it has written or engraved on it.

It should show most of the following:

A Brand Name - Wylex, Crabtree, MEM, Hager etc

A power rating - 100A, 80A, 63A etc

A trip sensitivity - 30mA, 100mA, 0.03A, 0.1A

A test button

A reset lever

A legend "Press to test" or "Test Monthly" or "Press down to reset" or "Turn to reset"

A part No. - AD100HED for example

 

[steve_warman]

Thanks for the info, I'll have a look tonight.
I know it has no test button on it.

 

[Steve]

true "main switches" dont trip. they are simply a switch and offer no protection of any sort. You must have an MCB or an RCD as the main switch.

 

[steve_warman]

Must be an RCD then.
But is there any advise on tracking doen the cause of this?

Thanks
Steve

 

[JohnD]

I think we'll find out what it is tonight.

Have a look at the cables that go to the lamps, and where they come from.

You say they tripped with the old lamps as well as the new ones, so it may well be a cable problem.

Look for any signs of water getting in, as they are outside; or of rodent gnawing.

See if there are any junction boxes. It is quite likely to be water penetration; or cable damage. There might be poor, or incorrect, connections. If you describe the circuit layout and components, as well as the switch that is tripping, we will think of likely causes.

I gather from what you say that the lights are spurred of the socket ring. Do you get tripping when the lights are switched off at the FCU? Or if the FCU is switched on but the cartridge fuse is removed from the FCU?

 

[TheGaffersSon]

Sounds like a rewire to me.

Light's are fed from the sockets?

No main switch

Constant tripping

Get the whole thing ripped out and start again. You probably have a series of age old problems, that could cost a lot of money and time to repair.

 

[RF Lighting]

Sounds like a rewire to me.

Not to me.

Light's are fed from the sockets?

Via an FCU, so thats ok

No main switch

Sounds like an RCD main switch, so thats ok

Constant tripping

Could be a very simple fault like water in a fitting, so thats ok

Get the whole thing ripped out and start again. You probably have a series of age old problems, that could cost a lot of money and time to repair.

What makes you say this? For all you know the wiring may be in tip top A1 condition, with a simple faulty external fitting.

 

[JohnD]

I bet his dad's taught him to suck his teeth, and shake his head slowly, as well!