Shower consumer unit

[smmjh11]

Hi I have purchased a shower CU with RCD and an MCB 50A. The shower they are buying is rated at 40/45A. The main CU is an old type that you pull the cartridges out (fuse wire).

From what I have seen on the shower instructions the main CU needs to have either an MCB or have a fuse fitted and I believe you can get an MCB that would fit this old type of CU. If I get a 40A MCB for the main CU would I then need to get a 40A MCB for the shower CU rather than the 50A that is currently inside. I will not be doing any of the electric work but just wanted to keep the costs down for him as the old shower it is replacing has nothing currently fitted that would come up to today's standards.

Many thanks

 

[deadshort]

Hi, your electrician will not connect the additional CU to the existing CU, they will split the supply from the meter into two and connect the new CU as a new circuit. The electrician will determine the size of MCB required depending on the installation design.

This is not a DIY wiring job.

Kind regards,

DS

 

[smmjh11]

Thanks deadshort for the quick reply. I was taking the information from a diagram from the shower manual which showed it going through the main CU. I won't get any more bits I will just hand over the unit to the electrician to sort out.

 

[deadshort]

Thanks deadshort for the quick reply. I was taking the information from a diagram from the shower manual which showed it going through the main CU. I won't get any more bits I will just hand over the unit to the electrician to sort out.

No problem, the diagram may have shown a separate RCD unit inline with the shower circuit. This is also a possible solution if you're existing CU will to take 45a MCB and the additional load.

DS