New DB instal in my house and rcd tripping please help

[Bruley88]

Hi all
I'mhaving trouble with a new instal its a spilt board 10 way DB
first half of the board has
down stairs lights
upstairs sockets
boiler
second half
kitchen
upstairs lights
and down stairs socket

The problem im having is the downstairs light in the hall is tripping the both rcd when turned on, I then removed the circuit from the rcd and wiring straight into MCB not touching the rcd just to fault find.when light is then turned on the rcd which is used to be run through doesn't trip but the second half of the DB trips the rcd although this rcd has nothing to do with the downstairs lights.
I have checked the factory wiring which runs from neutral terminal to top on both rcd each rcd neutral then runs to its own bar. I wired the circuit straight into the neutral terminal where rcds get there neutral feed from but still tripping second rcd.
sorry for rubbish explanation im a three phase and panel guy so this is abut out the ordinary for me any help would be great appreciated.

 

[mickys86]

Sounds like you have a borrowed neutral.

 

[ipf]

Seems like a common neutral. from a distance.

 

[Guest55]

i'd ask the electrician who installed it to come back and have a look.

 

[onions1066]

Borrowed neutral. Does it only happen when you use the hall light or when you put any load on any circuit, if it does you could have a neutral in the wrong bar causing an in-balance. If not your looking a the borrowed neutral situation, temp fix is to put both lightings on one mcb until you sort it

 

[spark 68]

Borrowed neutral. Does it only happen when you use the hall light or when you put any load on any circuit, if it does you could have a neutral in the wrong bar causing an in-balance. If not your looking a the borrowed neutral situation, temp fix is to put both lightings on one mcb until you sort it

True, but he would still have to put both Neutrals in the corresponding Neutral bar to that MCB's supplying RCD (correct side of the board), if that makes sense. :bucktooth:

 

[telectrix]

as above. posts. this problem usually occurs with 2 way switched lights, hall/landing/whatever. it's a common occurence and should have been sorted on the CU install. temporary fix.... take the bulb out.

 

[Octopus]

Who fitted it? They should know!

How do you wire it directly to the MCB bypassing the RCD?

 

[telectrix]

Electrical Trainee done a runner back to mummy coz. it don't work like they told me on day 7 of the course.

 

[Guest55]

stand down men , hes gone , the charades over , pants firmly pulled down.
next.
;-)

 

[glasgospark]

firstly the spark should be fixing this , he should have noticed this if he hung around long enough to atleast function test everything ,

guys above are correct borrowed neutral , should take less than 5 mins to rectify

 

[GLENNSPARK]

firstly the spark should be fixing this , he should have noticed this if he hung around long enough to atleast function test everything ,

guys above are correct borrowed neutral , should take less than 5 mins to rectify

what spark?...he`s done it himsen....
any spark competant to undertake board changes would know to IR test between neutrals beforehand...

 

[Bruley88]

Borrowed neutral. Does it only happen when you use the hall light or when you put any load on any circuit, if it does you could have a neutral in the wrong bar causing an in-balance. If not your looking a the borrowed neutral situation, temp fix is to put both lightings on one mcb until you sort it

It only happens with the hall light all other light down stairs work fine. I was thinking a borrowed neutral but didn't want to jump to conclusions. Well that the thing the light circuit is no longer on the rcd it's just run through the MCB but still knocking the second rcd off.

 

[Fast&Rough]

Get whomever fitted it back to fix it or stick both lighting ccts on the same rcd not ideal but better than nothing

 

[Octopus]

Time to come clean. Who fitted the board? what tests were done? Do you have an EIC? Was it notified?