7.5kw shower

[greasemonkey]

Currently has 6mm T&E feed from a 32A MCB
I need to replace the shower, but does my current setup need upgrading?

 

[rich.250]

Need to know more details before I can help you.
Length of run, new shower size, where the cable is installed.
Rcd protection?

 

[dook]

Would depend on the load of the new shower.

 

[dook]

.....as well as what rich.250 says!

 

[greasemonkey]

Need to know more details before I can help you.
Length of run, new shower size, where the cable is installed.
Rcd protection?

New shower 7.5kw
Run 10M
Cable run is under ground floor, all accessible from cellar.

Thanks @rich.250

 

[greasemonkey]

Sorry
No RCD

 

[Edd]

7.5kw at 230v == about 32 amps, and as the shower aint gona run all day, im gona go out on a lim and say its fine with what you have discribed. BUT!!! you will need RCD protection, no ifs no buts an RCD is a must...

 

[telectrix]

replacing shower on it's own . test the existing cable. if it is all sound, then no need to upgrade. RCD protection should be fitted , even if only a like for like replacement.

 

[rich.250]

Most showers are calculated at 240v
So i would estimate its a 7.2kw
So 31.25 amps.
I would say it sounds ok from the info on here.

 

[rich.250]

RCD a must

 

[telectrix]

i don't think there is a reg. in BS7671 re. RCD on a like for like replacement. however, the manufacturers instructions usually specify RCD, so that means you fit one.

 

[rich.250]

That was my thought telectrix

 

[Edd]

yer but im sure even if there aint no reg, if just replacing the shower it would make you sleep better at night and im sure you will be taking responsibility for the install so it should really need to comply..

 

[telectrix]

well. i would fit RCD, even if it meant fitting a stand alone unit next to CU ( assuming CU was rewireable 3036 fuses)

 

[SPARTYKUS]

Whats the actual voltage on site? Could be 223 or 254....

 

[greasemonkey]

Everyone. Thank you
This forum is great

 

[SPARTYKUS]

Yes it is.

 

[SPARTYKUS]

Ps r u doing it? Have you got calibrated meter to check RCD. Test button does not confirm it works properly with vindication, I would want it tested. I've fitted a fair few off the shelf that are duds.

Dont make em like they used to. I prefer the house brick ones

 

[Engineer54]

Ps r u doing it? Have you got calibrated meter to check RCD. Test button does not confirm it works properly with vindication, I would want it tested. I've fitted a fair few off the shelf that are duds.

Dont make em like they used to. I prefer the house brick ones

I'd have to disagree with that statement, RCDs if anything, HAVE improved over the years. But nowhere near to the point i'd trust/rely on them as my main form of protection against earth faults, as i've often stated on TT threads here. They still have a long way to go in the reliability stakes... lol!!

 

[SPARTYKUS]

You're allowed to disagree :86:

All I meant was, in my (not very) extensive research of trip times of 30mA RCDs, the oldest ones are without fail...faster.


As for reliability, I know not, i never fitted any so don't know if they were a bagg of ....nails off the shelf. Spose could/would have been!

 

[Engineer54]

You're allowed to disagree :86:

All I meant was, in my (not very) extensive research of trip times of 30mA RCDs, the oldest ones are without fail...faster.


As for reliability, I know not, i never fitted any so don't know if they were a bagg of ....nails off the shelf. Spose could/would have been!

You maybe right, but i wouldn't say that i've noticed that older RCD units being faster than the present day units. As far as i know, the same tripping and time requirements associated with 30mA RCD devices, have remained the same for many years now. Even then the accuracy isn't great!! lol!!

 

[D80]

The older RCD units (not got an image or a BS number for them to hand - sorry!) seem to be capable of lasting the test of time longer that the newer stuff. Lack of routine testing on the newer ones may be a contributing factor, but so many failing even mechanical tests that I come across. It's a sorry state of affairs they are so bad, especially in relation to TT systems when they can be all the more important. But with supplementary bonding starting to become a thing of the past due to RCD's its only a matter of time before someone is killed (hopefully an MP! Ideally House of Commons, whack the lot of them in one go!) because of failing RCD's.

 

[Deleted member 9648]

yer but im sure even if there aint no reg, if just replacing the shower it would make you sleep better at night and im sure you will be taking responsibility for the install so it should really need to comply..

While I would also be inclined to fit an RCD on a replacement as well....it's worth pointing out that just 4 years ago there was no requirement to RCD a shower at all....it could run straight off a 3036 fuse if you wanted......and everyone slept at night just fine.

 

[SPARTYKUS]

32 Amp MCB Will run at 35+ amps all day