Why does the UK use rings for sockets?

[telectrix]

Schneider produce rcbos with no neutral fly lead on their acti 9 isobar P DB’s, think the rcbo’s are only single pole tho.

no neutral or no earth?

 

[pc1966]

I don't see any need for them to be double-width, but for sure we should be moving to double-pole switching to make testing easier, and to have a neutral busbar arrangement in place so less effort and uncertainty in wiring the flying leads up.

There is the same problem for 3-phase where RCBO are rare and often need a 2nd slot for an add-one trip unit. Again, why not a neutral bar to all positions on the 3-phase system so you can have 3*single phase RCBO or 1 * three-phase, etc, per slot?

I have not played with the Schneider system to see how well it works, or if it addresses all of these things.

 

[Ian1981]

no neutral or no earth?

No fly leads on either

Isobar P is the first LV distribution board to have a plug-on RCBO (residual-current circuit breaker with overcurrent protection) capability. RCBO neutral and functional earth connections are usually wired into the neutral and earth terminals inside the distribution board, costing significant time by introducing additional wiring. With the new Acti9 Isobar P, installers can simply plug their RCBO directly into the board. This eliminates the need to cut, straighten or dress any excess wiring therefore reducing installation time by half.

 

[7029 dave]

Because we are British and don’t like change and have to do everything differently to the rest of the world

Because its ours. Long live the RFC

 

[Ian1981]

@telectrix

View: https://youtu.be/TUsbRGVVLP0


apologies if you can’t stand Nagy

 

[telectrix]

No fly leads on either

Isobar P is the first LV distribution board to have a plug-on RCBO (residual-current circuit breaker with overcurrent protection) capability. RCBO neutral and functional earth connections are usually wired into the neutral and earth terminals inside the distribution board, costing significant time by introducing additional wiring. With the new Acti9 Isobar P, installers can simply plug their RCBO directly into the board. This eliminates the need to cut, straighten or dress any excess wiring therefore reducing installation time by half.

not seen these as yet.

 

[Mike Johnson]

Contactum make dual pole RCBO's to international standard which in France, Switzerland and Germany it is a requirement to disconnect the neutral on activation: 40 Amp 30mA RCBO - 2 Module - Contactum - https://www.tlc-direct.co.uk/Products/CPBR402.html

 

[Ian1981]

not seen these as yet.

See link above
[automerge]1587651329[/automerge]

Contactum make dual pole RCBO's to international standard which in France, Switzerland and Germany it is a requirement to disconnect the neutral on activation: 40 Amp 30mA RCBO - 2 Module - Contactum - https://www.tlc-direct.co.uk/Products/CPBR402.html

2 modules is Far too big for some of the domestic CU’s and won’t fit in 3phase DB’s
Wylex and Crabtree do a single module type which is DP

 

[pc1966]

2 modules is Far too big for some of the domestic CU’s
Wylex and Crabtree do a single module type which is DP

I went with Wylex for that reason, but in my case it is more about ease of testing.

Another difference is in the UK a TT supply with a RCD incomer is relatively rare so you don't usually have to worry about a N-E fault tripping the RCBO and that, if single pole, will not isolate the N fault so the main incomer RCD might also trip.
[automerge]1587652030[/automerge]
Unfortunately the Wylex DP RCBOs are not approved for use in their 3-phase boards. Doh!

 

[Ian1981]

I went with Wylex for that reason, but in my case it is more about ease of testing.

Another difference is in the UK a TT supply with a RCD incomer is relatively rare so you don't usually have to worry about a N-E fault tripping the RCBO and that, if single pole, will not isolate the N fault so the main incomer RCD might also trip.

DP rcbos is definitely a consideration and necessary for that reason but you can have a domestic CU with just a mains switch isolator giving you your DP isolation and just single pole rcbo’s for the final circuits. Same principle for 3 phase, as long as the tails are subject to non movement and enter a ferrous material in a suitable gland etc, and are the insulated and sheathed type
[automerge]1587652277[/automerge]
[Unfortunately the Wylex DP RCBOs are not approved for use in their 3-phase boards. Doh!
[/QUOTE]
Why not?
If it’s because of them being only 6Ka then they don’t necessarily need to be greater than 6Ka, all would depend on the PFC and if there’s sufficient back up protection/ coordination if the breaker can’t break the fault current.

 

[pc1966]

Why not?
If it’s because of them being only 6Ka then they don’t necessarily need to be greater than 6Ka

Not the current, though 6kA is low for a TPN board. It might be the phase barriers are not up to 400V or something, but whatever the reason they are not listed by Wylex as approved.

 

[Ian1981]

Not the current, though 6kA is low for a TPN board. It might be the phase barriers are not up to 400V or something, but whatever the reason they are not listed by Wylex as approved.

Something to bare in mind, cheers.

 

[pc1966]

I could ask Wylex technical support about it, but I doubt I will get an answer until 2023 or so...

 

[Mike Johnson]

They are also made by Hager, Siemens and Schneider without flying leads, I have Hager three phase and neutral in my DB in France.
[automerge]1587654408[/automerge]
Hager two pole RCBO without flying leads: ESR RCBO B Curve 6KA 2 Pole Domestic Consumer Unit Circuit Breaker Electrical World - https://www.electricalworld.com/en/ESR-RCBO-B-Curve-6KA-2-Pole-Domestic-Consumer-Unit-Circuit-Breaker/m-2241.aspx
[automerge]1587654539[/automerge]
Sorry wrong link they are ESR not Hager.

 

[R-fur]

I prefer radials protected by RCBOs and would welcome DP ones if they could get them in a single module.