I had my house rewired 2 years ago and I asked the electrician to run in the wiring needed for an electric shower. The cable run length is about 20m and he has used 6mm T & E with a pull cord switch by the bathroom door. In the consumer unit he fitted a circuit breaker with NB150 B50 written on it. The main breaker is a CD284U 100A RCCB. My question is, what would be the maximum rated shower I could use for this installation. I am new to this forum so any help would very most useful