Square D Domae units

[Pensdown]

But that would then mean the installation would not comply with BS7671

why wouldent it? you can have a rcd as a main swicth

It does not comply with regulation 314-01-01 of BS7671 (16th ed)

Someone should write to the IEE and tell them they've made an error in Fig. 3a On site Guide and Fig. 3c IEE Electricians Guide to Building Regs.

Do you really believe it's Ok to use an RCD as an incomer, even for TT installations?

 

[sparkydude]

A few years ago all the MK MCB's used to be made by schneider and they were exactly the same as them. now that merlin gerin are part of the group i am pretty sure their rcbos will be a direct replacement for the domae range breakers. , they certainly look exactly the same. as the old mk ones used to .
Nick

 

[FingRinal]

But that would then mean the installation would not comply with BS7671

why wouldent it? you can have a rcd as a main swicth

It does not comply with regulation 314-01-01 of BS7671 (16th ed)

Someone should write to the IEE and tell them they've made an error in Fig. 3a On site Guide and Fig. 3c IEE Electricians Guide to Building Regs.

Do you really believe it's Ok to use an RCD as an incomer, even for TT installations?

Of course. And so do the IEE otherwise it wouldn't be a Reg. Even for TN sytems. Listed 2nd floor flat (TN) - 300mA RCD incomer mainly for fire reasons, what's the problem?

 

[Pensdown]

314-01-01 is an important Reg. But 'inconvenience' doesn't over ride preserving life, preventing fire, danger etc. in the event of a fault..

I would argue that "inconvenience" would be loosing all sockets. Loosing the complete installation due to a single earth fault is unacceptable. What if the earth fault was N-E on the fixed wiring? The customer would be without ANY power, lights, heating etc until the fault could be found and isolated.

A 30mA RCD as Main Switch is generally considered to be poor practice in a typical domestic installation and in conflict with 314-01-01, but I would suggest there can be exceptions.

I can't because earth leakage protection to 7671 can be incorpoated in the design without having a single point of failure.

 

[FingRinal]

It's a matter of design, risk assessment etc. That's why it's not against any Regs. Chapter 48 lists some situations.

It can equally be said that other design considerations can be used to alleviate the impact of an RCD main switch activating in the event of a single fault.

 

[streetlighter]

A few years ago all the MK MCB's used to be made by schneider and they were exactly the same as them. now that merlin gerin are part of the group i am pretty sure their rcbos will be a direct replacement for the domae range breakers. , they certainly look exactly the same. as the old mk ones used to .
Nick

I just looked at the MK RCBO on screwfix and they do have the same swiches as Merlin/Square D MCBs so i might get one and see if it fits correctly.
I need 1x16A and 3x6A but SF dont have the latter so its off to the wholesalers.
Im doing this to make my CU 17th compliant even though i dont need to as it was installed to BS7671 2004 16th edition regs.

 

[333rocky333]

Dont know if any use, square d make rccd's to fit that board , you would need two spare ways for each one you fit though.

As you know, proberly not a good idea to use just one for the circuits you want to cover.