Shower 'tripping' problem.

[cbr]

Hi People

Novice here.

Just moved into a new house and anytime the shower gets switched on and there are a number of other electrical appliances on, either the whole lot trips, lights, sockets, etc. or alternatively, only the sockets trip with the lights staying on.

The setup is as follows, bear with me and the extent of my knowledge.

The consumer unit as far as I can tell is an old thing, Crabtree Starbreaker 6100.
The MCB marked under the sticker 'Shower 32 Amp' is actually not a Crabtree MCB. I can't tell the make but it is 40 amps not 32. Another thing, I don't know if it makes a difference, but all the other MCB's are Type 1, whereas this is Type 2.

There are wires coming out of the consumer unit connected to a 40 amp RCD unit.
I am assuming this is the RCD for the shower because when I switch this off the shower doesn't work.

The shower is 8.5 KW.

Any ideas would be appreciated.

 

[JohnD]

Can you lay your hands on a digital camera and put up a pic?

When it trips, what is written on the thing that trips?

 

[didthathurt]

I've come across this a couple of times recemtly - both times it's been a (relatively) old shower and it was tripping the RCD. The manufacturer tells me it's quite common for the earth leakage to increase in showers with age up to the point where it will trip the RCD when the heater operates.