Electric Showers

[dragon3775]

I noticed that there was no mention of RCD protection in the shower circuits, it must noted that a rcd rated of at least 45 amp(30mA) is used to protect from electrocution. Especially when older home have little bonding or non at all in some circumstances.
A 40-45 amp circuit breaker is just not enough protection, where disconnection times are crucial.

 

[ban-all-sheds]

Thankyou for those words of wisdom.

We are all eternally grateful to you for bringing this important, yet puzzlingly little known, fact to our attention.

 

[breezer]

ban, you know that, i know that, but after all this is a diy forum.

thing is would you not agree that 45 amp(30mA)(taken from dragon3775's post) is confusing?

 

[ban-all-sheds]

ban, you know that, i know that, but after all this is a diy forum.

Yes - and the advice to use an RCD has been given here countless times, so anyone searching for "shower" will find it countless times...

thing is would you not agree that 45 amp(30mA)(taken from dragon3775's post) is confusing?

To say the least...

 

[dragon3775]

What is confusing my dear boy?

 

[dingbat]

Especially when older home have little bonding or non at all in some circumstances.

And of course, we are all aware that alterations and additions must not be made to an existing installation unless earthing and bonding arrangements are satisfactory. (Regulation 130-07-01 refers) So the notion of using an RCD because the bonding isn't up to scratch is misguided. The RCD is there because of the increased risk due to the lower resistance of wet skin, but if you are putting in a shower, not only do you have to supplementary bond the bathroom's extraneous conductive parts, in practice you also have to bring the entire installation's main earth and equipotential bonding up to scratch.

 

[breezer]

What is confusing my dear boy?

45 amp(30mA)

 

[AdamW]

Now, I am only a diyer, but I don't think I have ever seen a 45A 30mA RCD... a 40A yes, but a 45A no. I have seen a 45A MCB though...

Is this the big mistake? If so, do I win a prize?

 

[securespark]

Next size up from 40 is 63........

 

[dragon3775]

Next size up from 40 is 63........

Yes i agree my apologies, perhaps a 63 amp rcbo would be more suitable for a very high wattage shower unit.