RCD problems

[didcup]

just changed my consumer unit to a split load, i put all the lighting circuits on the switch side and the ring on the RCD side but the down stairs lighting circuit is tripping the RCD, any help

 

[JohnD]

lighting neutral connected to bar on wrong side of CU perhaps

or a borrowed neutral

You are aware that changing a CU is notifiable work under Building Regulations?

 

[didcup]

Thank you john D made the mistake before a long time ago of the neutral being on the wrong bar, decided to put a new feed in from the CU there being only 3 lights on the circuit and i am aware of the regs , thank you once again