rcbo

[paulrayner]

hi guys just been out to a job with a faulty rcbo and i noticed that when you swiched on the rcd (high integraty board) the rcbo tripped . the rcbo was feeding another board. has anybody come across this before? is this due to harmonic currents? any thoughts would be greatfull

 

[dixon9]

Hmmm...seems like a toughish one.

What cct(s) and equipment does this other board feed?

Have there been any new appliances added to this cct? Anything large and potentially dodgy such as a freezer/new kettle/oven?

 

[paulrayner]

Hmmm...seems like a toughish one.

What cct(s) and equipment does this other board feed?

Have there been any new appliances added to this cct? Anything large and potentially dodgy such as a freezer/new kettle/oven?

4 curcuits lights, ring, heating controlls & a radial with 1 fcu on it.
no new apps
ive retested everthing all hunky dory & put a new rcbo in everything works fine. only thing i can put it down to is the faulty rcbo but i still dont see why it triped when the rcd's were switched back on. the new rcbo dosen't do it. well it shouldent any way. thats why i was wondering if it was some thing to do with harmonic currents i know bugger all about them. just wondered if any of you guys could shed any light on it. but it seems not. oh well not to worry. at least I know its right and i can sleep

 

[dixon9]

4 curcuits lights, ring, heating controlls & a radial with 1 fcu on it.
no new apps
ive retested everthing all hunky dory & put a new rcbo in everything works fine. only thing i can put it down to is the faulty rcbo but i still dont see why it triped when the rcd's were switched back on. the new rcbo dosen't do it. well it shouldent any way. thats why i was wondering if it was some thing to do with harmonic currents i know bugger all about them. just wondered if any of you guys could shed any light on it. but it seems not. oh well not to worry. at least I know its right and i can sleep

Fair enough. Tested without the apps connected though? Just wondering if there was a dogdy element etc on one of the apps. Does it trip with none of the apps connected?

 

[supasparxs]

Did you shorten the Neutral flylead for the RCBO?
I phone Crabtree the other week and the minimum they say you can shorten it to is 150mm

what about the functional earth?

otherwise.....
?

 

[paulrayner]

Fair enough. Tested without the apps connected though? Just wondering if there was a dogdy element etc on one of the apps. Does it trip with none of the apps connected?

no everthing unplugged & dissconnected on both counts!

Did you shorten the Neutral flylead for the RCBO?
I phone Crabtree the other week and the minimum they say you can shorten it to is 150mm

what about the functional earth?

otherwise.....
?

Actually no I didnt shorten the leads. But im glad u mentioned this as ive often wondered but decided against as they usually have crimped ends so thought best not to. thanks for that.