shower feed

[freeflyer]

Hi all , got a catridge style CU with a single 45A 'powerbreaker' switch next to it that was once fed from the main CU. This 45 then went to the old stairlift in the house (overkill i know).

Anyway, we need to run a feed to the shower (10.5kw) . So, i know the CU is capable of supplying the 45A needed supply, but i'm unsure of the regulations.

Can we simply run a 10mm cable out of the catridge CU into a single 45A trip sitting next to it? then on to the shower? Or will we have to have something else done? Can i run the cable myself? or will an electrician have to do it?
Obviously i'm going to have it wired up properly by someone .. but i just wondered if we can get away with our current set up , and if so what work i can do myself beforehand.

ta..

 

[ban-all-sheds]

Hi all , got a catridge style CU with a single 45A 'powerbreaker' switch next to it that was once fed from the main CU. This 45 then went to the old stairlift in the house (overkill i know).

That powerbreaker switch is an RCD - the 45A refers to the maximum it can handle.

I'd be very surprised if the chairlift was on a 45A circuit....

Anyway, we need to run a feed to the shower (10.5kw) . So, i know the CU is capable of supplying the 45A needed supply, but i'm unsure of the regulations.

See above - you don't know that at all, unless the fuse on that circuit is 45A.

Can we simply run a 10mm cable out of the catridge CU into a single 45A trip sitting next to it? then on to the shower? Or will we have to have something else done?

That depends on what the fuse rating for that old circuit is, and if it's not large enough we are then into questions about whether your CU can support single loads of that magnitude. What is the rating of its main switch?

Can i run the cable myself? or will an electrician have to do it?

This work is notifiable, so the easiest and most cost-effective thing to do is to get an electrician. He might be OK with you running the cable, but that is something you'll need to sort out with him before you do it.

 

[freeflyer]

just checked, you're right, 45A stated on the switch but a 15A fuse in it.

Anyway, the main CU is as follows..

Total Max : 80A

Lights: 5A
Cooker: 30A
Sockets: 30A
Immersion heater : 15A (not used).

So, given that these all wont be on at any one time, can we safely draw a 45A off it? Obviously the total will hit 105A. If so, i'm assuming is it just a case of getting the feed off the bar and running it to the 45A breaker, and then on to the shower?
If we needed more a new CU, is it just a case of replacing it, or would some other work need to be done in order to knock it up to the required 105A?

 

[totoisacat]

What does CU stand for...just learning......thanks

 

[Softus]

It's short for CCU, which is an abbreviation for Consumer Control Unit.

In the olden days this was yer fusebox innit.

 

[totoisacat]

Thanks for that. I also read another thread that mentioned it and its what us amateurs call a fuse box i believe.

Modern ones have separate 'trips' to different circuits I believe-lights/cooker etc. I had one fitted to a place i have in France. excellent job done. By the way the French don't have rule about bathroom switches having to be pull cord. They argue that that the system/fuse will trip before anyone can be electrocuted. They found it 'funny' that i should be concerned. They were extremely good at their work so either the Brits or the French are wrong here....as an amateur don't know who is!

I need a new CU in my cottage in Dorset I think. I have a very old system. There don't seem to be separate fuses for different appliances. It is a small place with couple of old storage heaters on a cheaper circuit/meter. I want to modernise the CU and ada separate circuit for an electric shower but don't understand 'amps' etc. I know about watts but not a clear theoretical understanding of electrics. Know of any good books?! Or web references?

 

[Softus]

There's a lot of information in the Wiki on this site.

Aim to understand the significance of current rating and heat dissipation, of fusing and other protective devices, and of earthing systems. If you do that then you'll be several steps ahead of the French.

 

[totoisacat]

What is Wiki?!

French aren't that dumb ( my son is half french and wife 100%) !

I understand the terminolgy but not a real understanding of the way electricity works.....i realise overheating of wires causes fire etc and roughly about amps and watts but not 'real' undersatnding...will get there though! Where there is a will....

 

[ban-all-sheds]

By the way the French don't have rule about bathroom switches having to be pull cord.

Neither do we.

I want to modernise the CU and ada separate circuit for an electric shower but don't understand 'amps' etc. I know about watts but not a clear theoretical understanding of electrics.

Then if you want your upgrade to be timely you should get an electrician.

Know of any good books?! Or web references?

//www.diynot.com/forums/viewtopic.php?p=75416#75416

Where there is a will....

....there's a beneficiary.

 

[Softus]

Can you see what it is yet?

 

[Pensdown]

It's short for CCU, which is an abbreviation for Consumer Control Unit.

In the olden days this was yer fusebox innit.

Can you see it yet?

//www.diynot.com/wiki/electrics:abbreviations

 

[totoisacat]

Many thanks for those 'pointers'....the depth of knowledge required comes a s abit of a 'shock' to me. As much as i would like to get to grips with it all i have to balance out the time it takes against employing someoneto do the work.
I decided to 'do up' and annex next to our cottage in Dorset and thought i would obtain Builder Certificate from Local Authority but realise now that i am letting myself into a lot of hassle as everything has to be perhaps too regulated and costly as a consequence....the actual building/plumbing i can handle-its not rocket science-but the electrics is more 'demanding' and i will most probably get someone in having heard all the comments and advice here. I will speak to the Building officer though first...see if i can do any work if supervised on this board, and then have the local authority check it...see how it works out finacially. The costs all add up and am strapped for cash at present, hence doing all the work myself.

 

[Softus]

//www.diynot.com/wiki/electrics:abbreviations

Yeah the Wiki is wrong in that respect.

 

[Pensdown]

//www.diynot.com/wiki/electrics:abbreviations

Yeah the Wiki is wrong in that respect.

Yeah..whatever

 

[securespark]

How about adding

CCU - consumer control unit

FLC - full load current

And then add Ze, Zs & Zdb to the definition of "Z"??