Zone 1 under bath tub

[Simonslimline]

It changed when the byb came out its now zone one all the time now

I feel you may have misunderstood/read this part of the regulations Joe.

My BYB clearly states that - The space under the bath tub or shower basin is considered to be zone 1. However, if the space under the bath tub or shower basin is only accessible with a tool, it is considered to be outside the zones.

Conclusion Nothing has changed in BS7671 from previous to current AMD3.

:50:

 

[Deleted member 26818]

. The OP is talking about a circuit external to the location but passing through it, and outside the zones, so no RCD required.

i am aware that the OP is talking about a circuit external to the location but passing through it.
It does not matter that it passes through the location outside of any zones, it still passes through the location.
It requires now in the 17th edition just as it did in the 16th edition, additional protection.
However the additional protection required now is solely by means of an RCD.

 

[Octopus]

Conclusion BS7671 is written by idiots

:50:

Corrected that for you.

 

[Simonslimline]

Corrected that for you.

Yep that as well lol.

 

[sparksburnout]

i am aware that the OP is talking about a circuit external to the location but passing through it.
It does not matter that it passes through the location outside of any zones, it still passes through the location.
It requires now in the 17th edition just as it did in the 16th edition, additional protection.
However the additional protection required now is solely by means of an RCD.

Taken from the Stroma guide to 3rd AMD: Bathrooms - There is already a requirement for all low voltage circuits in a bathroom to be 30mA RCD protected. There is now a new provision requiring low voltage circuits passing through Zones 1 and 2 of a bathroom to be 30mA RCD protected.

 

[HandySparks]

Taken from the Stroma guide to 3rd AMD: Bathrooms - There is already a requirement for all low voltage circuits in a bathroom to be 30mA RCD protected. There is now a new provision requiring low voltage circuits passing through Zones 1 and 2 of a bathroom to be 30mA RCD protected.

Just looked it up. You're right.
'701.411.3.3 Additional protection by the use of RCD ... shall be provided for low voltage circuits
(i) serving the location
(ii) passing through zones 1 and/or 2 not serving the location.'

Can't see any specific requirement for cables passing through outside the zones.

 

[DPG]

Taken from the Stroma guide to 3rd AMD: Bathrooms - There is already a requirement for all low voltage circuits in a bathroom to be 30mA RCD protected. There is now a new provision requiring low voltage circuits passing through Zones 1 and 2 of a bathroom to be 30mA RCD protected.

Interesting - I must admit I thought it referred to any cable passing through a bathroom - didn't realise it was limited to within zones 1 and 2 only. Daz

 

[Dave OCD]

Interesting - I must admit I thought it referred to any cable passing through a bathroom - didn't realise it was limited to within zones 1 and 2 only. Daz

Me too

 

[Deleted member 26818]

Apologies, I have yet to obtain a copy of the 3rd amendment.
The pre amendment wording is: "Aditional protection shall be provided for all low voltage circuits of the location, by use of one or more RCDs having the characteristics specified in Regulation 415.1.1."

I was aware that many people believed this requirement only applied to circuits which served the location, and were unaware that it also applied to circuits just passing through.

I'm pleased that the IET have taken measures to clarify matters, though I am surprised that they have decided to limit it to only circuits which pass through zones.