Shower pump wiring

[The Lazy Slug]

Afternoon All,

Just after a little advice on the wiring for a shower pump.

The pump will be in the same room as the shower, but over 0.6m away and in a cupboard.

I'm thinking of doing one of two following options.

1. Running a spur from the ring main via a 45W pull cord isolating switch to a fused 30MA RCD, where the shower would be connected.
2. Again running a spur from the ring main but this time to a switched FSU in the cupboard and rely on the RCD on the ring main, providing it's 30MA (Can't check it at the moment.)

Option 2 would save sometime, but I just want to check the legality of it first (ie a 'switch' instead of a 'pull cord')

From what I have read I realise this will have to be certified, but my electrician is away for three weeks (yes, there are some parts of the world were mobiles are useless! )and the plumber wants to start Monday!

Thanks very much

The Lazy Slug

 

[telectrix]

option 2. FCU off ring. it,s only a pump. fuse FCU at 3A or 5A . go by manufacturers instructions. FCU in cupboard is fine. ( you only need 45A switch for instantaneous showers which pull around 40A)

 

[The Lazy Slug]

Wow! quick response! Thanks very much telectrix.

You answer has made me think of just one other question, if I can please?
If the RCD on the Ring Main is NOT 30MA, would I be required to fit one on the spur?

Thanks again

 

[ezzzekiel]

is there currently an rcd protecting the circuit? if not fit an rcd fused spur cost around £15

 

[The Lazy Slug]

There is a an RCD but I'm sure of the rating. (Going to check it when i get home to get the MA value.) From the regulations I've read, it should be 30MA for a shower, not higher. (although that may actually only apply to power showers, not pumps.)

 

[telectrix]

should be 30mA anyway. some older TT installations have 100mA. as ezzzekiel says, if 30mA, fine. if not use a 30mA FCU just for your shower pump. don't forget, if you are reluing on existing RCD, test it, also Minor works cert. for the modifiewd circuit which should have RCD trip time/s entered on it anyway)

 

[antimatter]

should be 30mA anyway. some older TT installations have 100mA. as ezzzekiel says, if 30mA, fine. if not use a 30mA FCU just for your shower pump. don't forget, if you are reluing on existing RCD, test it, also Minor works cert. for the modifiewd circuit which should have RCD trip time/s entered on it anyway)

Older installations?

 

[The Lazy Slug]

Just got home and I have a 30MA RCD on the consumer unit - I'll test it before starting work (IE when my wife isn't cooking my supper! )

Many Thanks Everyone for all your help