Keeps Tripping

[carl9254]

installed a PIR Outside light today, took supply from landing light to a junction box, live down to switch and back upto junction box as swith live, then switch live, neutral and earth out to light. The light did its test and seemed fine and the downstairs lights swithed on too. So went away happy, few hours later got a phone call back, the MCB had tripped, the guy came back to his house while dark, the outside light worked but as soon as he went in and switched landing light on it tripped the MCB and it wont reset, you just see a blue spark everytime you try to reset????

HELP???

 

[Guest123]

Hi.

Well the blue flash suggests a short circuit somewhere.

Could be a pinched conductor somewhere, best thing to do is re-check all your terminations and fixings etc.

P.S what is the loading on the circuit???

 

[carl9254]

Not much, 5 9w lights and the new 60w outside light, if I diconnect my new circuit from supply end should it reset??

 

[Dannyg83]

if u put landing light switch in off position it will probably reset

 

[Guest123]

You havn't taken line off upstairs and neutral off downstairs have you???

 

[lister]

Has it rained since you fitted it ?

 

[pushrod]

You havn't taken line off upstairs and neutral off downstairs have you???

that would trip an rcd, but would it trip an mcb? OP says it's an mcb that's tripping out.

reckon your first suggestion of a short and checking terminations, especially in the JB, is the most likely.

 

[kduck]

sounds like water in it to me too. It would trip the mcb.

 

[Guest123]

Just trying to throw some Q's in there.

 

[pushrod]

sounds like water in it to me too. It would trip the mcb.

would the outside light have come on in the first place? It was the internal switching that tripped the mcb.

 

[Dannyg83]

Short at landing light for me , nothing to do with water , he tried to switch on landing light and the mcb tripped first place i would check

 

[carl9254]

All switches are in off position and it still wont reset. Dont think its rained since. As soon as i switched it on the light did its test to detect whether daylight or not then it didnt come on till the guy came home at night, he went in his house and put landing light on and then it tripped. The landing light defo worked before i went home.

Thanks everyone.

 

[pushrod]

Will it reset when the power is off?

If it's a switch/push button type mcb i've known them to be quite finicky when resetting. The switch must be pushed firmly down before the button can be put in and then the switch can be reset.

 

[Yooj]

Hi Carl,

Was this that job you were talking about the other day in terms of ways of doing it, time it took you etc?

If so, how close were you to your time/materials estimate?

Don't worry about the fault-finding on this...happens to all of us at some point...It is likely to be a simple fault which you will find straight away.

Yooj

 

[beanzntoast]

IMO nothing to do with water as this would also trip the RCD,As lenny said i would start from the begining re-check all your connections/terminations especially in you juction box could be just something as simple as that