Circuit breaker problem.

Soldato
Joined
19 Oct 2002
Posts
6,588
Location
Bath
No but it may have existed before hand. Could also be the source of your small draw.

Very common to have a borrowed neutral on a lighting circuit in flats/converted houses.
 
Soldato
Joined
12 Apr 2007
Posts
10,488
The RCD will always trip. Think of it a bit like a slave master switch.
You just need to do a logical process of elimination...

Switch everything off on the fuse box. Then switch the RCD on. Then eliminate the circuits one at a time.
 
Soldato
Joined
1 Mar 2010
Posts
17,398
maybe reiterate what happens ? that the RCD does indeed trip taking out other appliances when you try to switch the lighting circuit back on.

if (tomorrow) you turn off all the cicruits , does the lighting circuit alone then work ?
so as Bigboy suggested you may have another circuit that is leaking charge into the lighting circuit when it is switched on as well,
so turn the others on and off individually until you find it.

my suspect, like I mentioned might be the one with the UPS - if you have now permanently turned off the immersion switch it can't be that.


as you say, it all sounds weird that you have done nothing to reconfigure the appliance connections in the house and the problem has started unprovoked, maybe when you had turned of ups circuit earlier it started having a problem

e:
It's the mcb that won't stay on isn't it, not the rcd from how I'm reading op?
I agree it's not clear
 
Soldato
Joined
27 Feb 2015
Posts
9,604
It's the mcb that won't stay on isn't it, not the rcd from how I'm reading op?
Correct.

I considered getting my own electrician as I am sat here waiting but seems it wouldnt be particurly cheap, so until someone comes out (rented) there is no conclusion to this at the moment.
 
Soldato
Joined
27 Feb 2015
Posts
9,604
maybe reiterate what happens ? that the RCD does indeed trip taking out other appliances when you try to switch the lighting circuit back on.

if (tomorrow) you turn off all the cicruits , does the lighting circuit alone then work ?
so as Bigboy suggested you may have another circuit that is leaking charge into the lighting circuit when it is switched on as well,
so turn the others on and off individually until you find it.

my suspect, like I mentioned might be the one with the UPS - if you have now permanently turned off the immersion switch it can't be that.


as you say, it all sounds weird that you have done nothing to reconfigure the appliance connections in the house and the problem has started unprovoked, maybe when you had turned of ups circuit earlier it started having a problem

e:

I agree it's not clear
Nope, The RCD isnt tripping, the lights are not even linked to an RCD from what I can tell.

The RCD is green, and seems to be linked to my sockets and shower.

Then all the red switches are lights, lights, immersion and oven then at the end is a red master switch.

The switch thats tripping is the first lights switch, RCD stays on, everything else stays on.

If the mains is off, the lights switch still trips, it has all the ballparks of a failed circuit breaker/switch.

I can post a photo but the labels wont be readable as the angle and distance to the box doesnt get proper focus.

I can try the new test you have suggested of which I try to only turn on the lights switch by itself.

I am not sure though why you think a UPS is tripping a lights circuit on a different circuit and this problem would start simply from turning the lights switch off then on again.

--

Done the test

This will probably be the last one as I dont want to keep switching everything on and off now.

I turned off all switches gradually, then with all of them off including the master tried to turn on the first lights, it wouldnt stay on.

I then turned on the master and tried to turn on the lights by itself with the master on, wouldnt stay on.

Have now turned the rest back on.

Also the lights switch that wont turn on always clicks when I push it up, whilst the others dont.
 
Last edited:
Soldato
Joined
28 Dec 2017
Posts
6,416
Location
London/Beds
If it won't stay on when the main power is off... That doesn't sound electrical, that sounds mechanical. You're saying here that nothing is tripping, the switch just won't stay up?

Last year I had similar and it turns out I just needed to push the MCB up harder...
 
Soldato
Joined
27 Feb 2015
Posts
9,604
So an electrician came, he started checking the light fitting, but then I told him what happened so he immediately went to the trip switches, within 5 minutes diagnosed as the switch, the two light circuit's have been merged to the good switch. Apparently my board is also ancient. :p He appreciated the diagnosis I already did as it saved him a lot of time.
 
Top Bottom