Perhaps I am being over protective but
Why is it not necessary to have an RCD on the supply to the cooker.
If the protective earth to the cooker failed for some reason and the cooker developed a live to chassis fault ( leaking element ) then the chassis is live. Some ones touches the cooker with one hand and an earth bonded piece of metal with the other. As the cooker chassis is live that person has the immediate need of an RCD dis-connect.
Also the 30 ( 0r 100 ) mA fault current that would trip the RCD in a fault condition is not going to cause any damage where as a fault current that could reach 30 amp before the MCB tripped could do damage to metal work or wiring not designed to carry 30 amp. Not all wiring in cookers is capable of sustained passage of 20 amps or more.
( our oven IS on an RCD and the kitchen lights are on a different RCD )
Bernard
Sharnbrook
Why is it not necessary to have an RCD on the supply to the cooker.
If the protective earth to the cooker failed for some reason and the cooker developed a live to chassis fault ( leaking element ) then the chassis is live. Some ones touches the cooker with one hand and an earth bonded piece of metal with the other. As the cooker chassis is live that person has the immediate need of an RCD dis-connect.
Also the 30 ( 0r 100 ) mA fault current that would trip the RCD in a fault condition is not going to cause any damage where as a fault current that could reach 30 amp before the MCB tripped could do damage to metal work or wiring not designed to carry 30 amp. Not all wiring in cookers is capable of sustained passage of 20 amps or more.
( our oven IS on an RCD and the kitchen lights are on a different RCD )
Bernard
Sharnbrook