rcd tripping on switching shower on

[phonic1]

hi
just retro fitted a shower rated at 8.5KW. 6mm cable already present and clipped to inside wall. new mcb and rcd fitted and insulation tests performed.
there is power light on at shower yet when shower is switched on the rcd trips every time??????? can anyone help???
the distance is about 10M max and don't know weather there is a phase inbalance. TT system.
would be grateful if anyone could advise thanks

 

[viewer]

Cream crackered heater/boiler?

 

[phonic1]

its brand new and exchanged it for new one of same barnd 'triton passion' but still trips!!!
i'm at a loss

 

[xr4x4]

Was the wiring, mcb and rcd already there and working before you fitted the shower?

 

[ban-all-sheds]

there is power light on at shower yet when shower is switched on the rcd trips every time??????? can anyone help???

Yes - an electrician onsite to sort out the cockup with the new MCB & RCD.

don't know weather there is a phase inbalance.

 

[Taylortwocities]

3 phase shower?

OK back to basics.

WHat happens if you connect a different load instead of the shower (a light eg). Does it still trip?

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