9.5 kw shower

[ban-all-sheds]

I notice that there is no provision for an earth connection on either the RCD or back box, only live and neutral.

That's right - RCDs don't need or use an earth connection.

And if the enclosure is plastic, it doesn't need to be earthed.

But surely there is an earth bar in the MK enclosure?

 

[balrog]

Hi Folks,

No, there is no earth bar in the MK Sentry enclosure!

Bob

 

[balrog]

Hi folks!

I am just about to position the shower cable and earth wires withing the electrical cupboard prior to connection. Could you please advise on the point at which these wires should be connected, so i can route the cables accordingly.

I have an old style fuse box with wired fuses. This is fed from a RCCB circuit protection device which is connected to the meter. The shower will be protected with a 40 amp RCD. Can the RCD be fed from the fuse box and if so, what size fuse would be needed. If the 'old style' fuse box cannot support such a load, where should the RCD for the shower be fed from?

Many Thanks

Bob

 

[Juno 60]

I would connect your shower to a seperate dedicated CU (get a shower CU from Screwfix) which has its own RCD and 45A or 50A MCB. Split the supply to your existing CU and the new shower CU using a Henley block.

 

[Juno 60]

I would connect your shower to a seperate dedicated CU (get a shower CU from Screwfix) which has its own RCD and 45A or 50A MCB. Split the supply to your existing CU and the new shower CU using a Henley block.

 

[securespark]

No. 2 - 4 module enclosures generally have no terminals in them whatsoever.

If you are really clever, you can terminate your cable inside the enclosure without breaking the earth conductor.

This would ensure perfect continuity, obvioiusly....!

 

[ban-all-sheds]

Hi folks!

I am just about to position the shower cable and earth wires withing the electrical cupboard prior to connection. Could you please advise on the point at which these wires should be connected, so i can route the cables accordingly.

I have an old style fuse box with wired fuses. This is fed from a RCCB circuit protection device which is connected to the meter.

So you already had earth fault protection. What rating is the RCCB? You might not have needed the new RCD..

The shower will be protected with a 40 amp RCD. Can the RCD be fed from the fuse box and if so, what size fuse would be needed.

We've been through this before! Can you do simple arithmetic, like 9500/230, hopefully getting the answer 41.3? i.e. you need 45A or 50A protection.

You can't use a rewirable fuse as (AFAIK) you can't get 45A fusewire, and even if you could, the carriers are not designed to handle more than 30A.

You might be able to use a plug-in MCB - you can get those in 45A or 50A, but if the main switch of your fusebox is only rated at 60A, then you won't be able to use one, as the fuseboard is simply not designed to handle loads like that.

The best way is as Juno said - have a mini-CU with an RCD and a 45A/50A MCB fed from the meter, with the tails split i a Henley block. This will need the tails to be isolated by pulling the service fuse - not a job for you - get an electrician in.

 

[plugwash]

never seen a 50A plug in

wylex plug ins come in up to 40A
ge mini trips (which are inteded as replacements for wylex boards) come in up to 45A
note that with GE mini trips you have to buy the base seperately

the rcd after the CU should be the next rating above this which is 63A

afaict if you fitted it near the bathroom you could use the RCD *AS* the isolating switch

 

[balrog]

Hi folks,

Thank you all for your input.

My house is already fitted with a MEM RCCB. The ratings marked on it are as follows: 80 amp - 30ma - 240v. The shower is rated at 9.5kw 240v. It is stated on the RCCB that the unit only protects circuits.

Would this unit actually be able to protect the shower as well? The paperwork with the shower states that it should be protected by a 30ma RCD.

The shower also has a 50 amp twin pole switch in the bathroom on a pull cord.

I will be having an electrician check it all over and do the connecting. I don't mind running cables in but that's about my lot!

Many thanks

Bob

 

[ban-all-sheds]

Hi folks,

Thank you all for your input.

My house is already fitted with a MEM RCCB. The ratings marked on it are as follows: 80 amp - 30ma - 240v. The shower is rated at 9.5kw 240v. It is stated on the RCCB that the unit only protects circuits.

Would this unit actually be able to protect the shower as well? The paperwork with the shower states that it should be protected by a 30ma RCD.

 

[securespark]

Hang on though. If it is an RCCB, as opposed to an RCD, it is an old board.

Is the RCCB the main incomer? The main switch for the CU? If so, it may be better to feed the shower with a sep. unit to avoid overloading it.