ive had a new oven fitted it is wired into the kitchen ring main thru a fused double pole switch the ring main goes back to the consumer unit which is protected by a 63 amp rcd when the oven is switched off the rcd trips but the fuse and cb are ok some times the rcd dosnt trip and some times it does but never when its switched on onlly when switched off nothing else in the kitchen has this effect please help
Presume you mean it trips when switched off at spur, not on oven control sw.? If so why do you keep switching it off there?
The problem may be that if double pole switch breaks Neutral slightly before Live as they can sometimes do then RCD can see loss of neutral & any slight leakage from oven will cause trip, hope this helps ,
One other poss. recheck earth connection is good & tight, in fact all connections, RCD's can be fussy, tho' normally if cold / damp, trip on sw. on, not off!
To really check it out need I.R. tester and earth leakage 'clamp meter' around earth core only to measure mA loss or around L & N but not earth to see imbalance, not much help, sorry,SPARX