Circuit breaker trips

[StuDH]

Over the past few days, our upstairs lighting circuit breaker has been triping out about twice a day. It's not triggered by something being turned on, it's pretty random.
The house was rewired about 4 years ago, so I don't think it's dodgy wiring.
Do you get faulty MCB's, - should I have that changed?
We use energy saving light bulbs, could a dodgy one of these cause the problem?

Thanks Stu.

 

[riveralt]

You can get faulty MCB's but very rarely.
It is more than likely a loose terminal connection at one of the lighting units or switches - EDIT which (to satify Bernard) has led to a loose conductor short circuiting.
Alternatively, and I'm starting to see this a lot now, a damaged lamp especially where the old incandescent has been replaced with a energy saving one and there is insufficient space between the lamp unit and the lamp shade.
You will need to check each terminal and lamp along the circuit route.

I take it you haven't changed anything recently?

 

[bernardgreen]

It is more than likely a loose terminal connection at one of the lighting units or switches.

How would a loose connection INCREASE the current ? It would reduce the current.

Unless it is so loose that the wire has come out and is now shorting to something.

 

[StuDH]

Thanks.
Nothing has been changed. The fault just started on it's own.

I'll check the light fittings.

Stu.

 

[Steve]

I did have a dodgy cable on my rewire. Along its length somewhere it was shorting switched live to earth. But this only manifested itself about a month after the rewire.

 

[jpread988]

If your mcb it tripping a couple of times a day and your are not switching anything I would think there problem is a thermal trip, as said before prob loose connection (arcing)