RDC faulty?

[curious67]

My cooker is wired through MCB the a RCB. When both are off but other circuits are on (ie the main switch is on) I get 8v ac between live and earth. Is this normal? (the RCD seeams to work as expecteds). It only goes to zero only when the mains is swithched off. My Ac meter is good. My only explanation other than a fault is some funny wiring inside the RCD ? Any ideas. I dont want to get (pay) for an electrician unless I have some evidence of an actual fault.

 

[Steve]

where do you measure this voltage? how are the MCB and RCD arranged? in a CU together? (split load?)

 

[Adam_151]

What is your earthing arrangement? TT, TNC-S, or TNS?

 

[curious67]

deleted should have been on another wrong thread

 

[curious67]

Supply is TNS, The MCB & RCD are both in a Proteus CU. I measured the voltage directly across the Earth & live leads at the cooker isolator.