415v 3 phase sockets and rcd protection.

[simpson93]

Afternoon all,

Looking for a little guidance, other than doing sub mains in armoured I don’t do much three phase work.

I’m looking to install some final
Circuits for some three phase cooking equipment but I find myself stuck on a few things, as the sockets will be over 16amp they will need to be rcd protected but I can’t seem to find anything to find a Hager board rcbo etc. What’s the best way to protect it?

Also generally if doing a three phase sub main I would take an additional earth as I’m not so keen on solely relying on the armoured earth. Do most people generally rely on the armoured earth or use 5core?

Thanks for your help

 

[Norah Nabino]

I suggest you read back through the thread from the start!
I have only given constructive advice!
Please prove otherwise..
I have been involved in the installation and repair of commercial catering equipment for 25 years, I am an approved engineer for many brands.
What has been suggested is totally unnecessary..
just because you can’t do something doesn’t mean that it can’t be done, a risk assessment in this instance would be easy enough..
It’s stationary equipment that doesn’t need RCD protection

Are you sure about what you are saying here??
Are you uo to date with BS7671???

 

[Norah Nabino]

I suggest you read back through the thread from the start!
I have only given constructive advice!
Please prove otherwise..
I have been involved in the installation and repair of commercial catering equipment for 25 years, I am an approved engineer for many brands.
What has been suggested is totally unnecessary..
just because you can’t do something doesn’t mean that it can’t be done, a risk assessment in this instance would be easy enough..
It’s stationary equipment that doesn’t need RCD protection

Are you sure about what you are saying here??
Are you uo to date with BS7671???

 

[Norah Nabino]

I’m not disputing the need for a plug and socket only the need for RCD protection..
Up until now equipment in this environment hasn’t needed to be considered for RCD protection..

You need to read the regulation 411.3.3.

 

[Norah Nabino]

I’m not disputing the need for a plug and socket only the need for RCD protection..
Up until now equipment in this environment hasn’t needed to be considered for RCD protection..

You need to read the regulation 411.3.3.

 

[Norah Nabino]

How can you guarantee that the person unplugging the equipment will be instructed?
How can you guarantee that the equipment will always be plugged back into the same socket-outlet?
What difference would it make whether the equipment is or isn’t plugged back into the same socket anyway?

Exactly

 

[Nigel]

Are you sure about what you are saying here??
Are you uo to date with BS7671???

Are you?

 

[Norah Nabino]

Are you?

Of course.

 

[bernie4253]

I got bored with all the cat fighting and haven't read the entire thread, so forgive me if I've said something that has already been said.

If you decide RCD is the way to go, Hager do a range of three-phase RCD's. They are not cheap, but you can often find them on ebay.fr second hand. There is nothing wrong with them. They are usually from domestice installations in the rural areas which are often three-phase and some UK sparkies change them to single-phase so the RCD's are just surplus. Search for "Hager differentiel tetra"

 

[Charlie_]

Hi Norah
Thanks for the advice on reading the regs..
In a commercial kitchen where would you put a 3 phase RCD protected socket to protect a piece of stationary equipment; such as say a twin deep fat fryer or a 20 grid combi oven?
That little book you hold so dear hasn’t got all the answers, what will you do now?

 

[Toneyz]

I’m not disputing the need for a plug and socket only the need for RCD protection..
Up until now equipment in this environment hasn’t needed to be considered for RCD protection..

Yes, but this all changed with the 18th.

 

[Ruairi Hansen]

Install a 32A 3 phase rotary switch instead?

 

[EalingBadger]

Given the propensity of electric heating elements inside catering equipment to break down to earth I would want to fit RCD protection regardless. Better that (and an annoyed customer as the RCD starts tripping intermittently in the future!) than the black mess that will result from the circuit not disconnecting until the MCB pops.

 

[Charlie_]

Satisfactory Zs readings would be an essential requirement of any RA

 

[Toneyz]

Install a 32A 3 phase rotary switch instead?

Whilst this would be ideal so not having a socket neglects the need for RCD protection, the OP has stated that he is required to provide si=ockets.