3 phase to single phase

[simon helstrip]

what sort of connection do i need to go from a 32a 3 phase down to a 13a single phase?

 

[Pete999]

what sort of connection do i need to go from a 32a 3 phase down to a 13a single phase?

1 Phase and 1 Neutral plus an Earth plus the relevant fusing arrangements

 

[Spoon]

As above.
What is your situation?

 

[davesparks]

This sounds like an event type situation where you’ve got a 32A TP socket but only need a 13A socket?

If this is the case then you need to hire or buy a ‘distro’ (distribution box) which has a 32A TP incomer and some 16A SP outlets and then use 16A - 13A distro or adaptors to get what you need.

 

[Darkwood]

I would query if there is a neutral, info is a little vague here, is this a distribution or a socket outlet ?

 

[I2C]

Completely agree with previous comments.

However I'm a little concerned that you've asked this question, given the increased-dangers of three-phase, while the answer should be common-knowledge for a competent person.
Please don't be offended by this, perhaps there's more-to-it and a bigger question to answer, but if you're not competent at performing the work then for your own safety I'd recommend hiring someone to help.

Also, don't forget other relevant considerations (for example: socket-outlets under 20A require additional-protection, like a 30mA RCD; or balancing the phases; etc).

 

[Darkwood]

@I2C

Also, don't forget other relevant considerations (for example: socket-outlets under 20A require additional-protection, like a 30mA RCD; or balancing the phases; etc).[/QUOTE]

Can you specify regulations on this?

 

[I2C]

Can you specify regulations on this?

I'm surprised you asked, but of course:

BS7671 Amendment 3 411.3.3 'Additional Protection' (i) states:
"Additional protection by means of an RCD in accordance with Regulation 415.1 shall be provided for:
(i) socket-outlets with a rated current not exceeding 20A"

BS7671 Amendment 3 415.1 'Additional Protection: Residual Current Devices (RCDs)' 415.1.1 states:
"The use of RCDs with a rated residual operating current (I delta N) not exceeding 30mA..."

I hope this helps

 

[Darkwood]

Was more relating to the balanced phases tbh, just pulled the paragraph as a whole, I agree it is good practice to balance phases as it can give more scope for 3phase future loading but I'm not aware of any regulations that state it has to be done?

PS I build machinery controls so the reg's I follow sometimes take me away from the BS7671 and I occasionally get mixed up, I had it in my head it was 32amp for rcd protection although I will concede to your provided info and will double check myself

 

[I2C]

Was more relating to the balanced phases tbh, just pulled the paragraph as a whole, I agree it is good practice to balance phases as it can give more scope for 3phase future loading but I'm not aware of any regulations that state it has to be done?

Fully understood and I agree with you. Upon further investigation, I'm unable to backup my statement regarding phase-balancing with any regulations, and therefore I stand corrected.

It seems strange that there doesn't appear to be any requirements in the regulations regarding phase-balancing, but rather 'good-practice' in order to save the client money on their electricity bill.

I digress, so back to topic. It's clearly easy to naively come to conclusions as I've shown. Therefore, be cautious and honest with your capabilities.

 

[David M]

@I2C

Also, don't forget other relevant considerations (for example: socket-outlets under 20A require additional-protection, like a 30mA RCD; or balancing the phases; etc)

Can you specify regulations on this?

Although not regulation I believe its a fair comment regarding "consideration" for phase balancing. The rest of the post was, in my opinion sound advice for the original poster.

 

[Darkwood]

Although not regulation I believe its a fair comment regarding "consideration" for phase balancing. The rest of the post was, in my opinion sound advice for the original poster.

Totally agree, it was just the ambiguity of the wording that gave the impression it was a requirement hence I queried it but yes where possible having balance gives better scope for future additions of 3ph equipment, it won't save any money on energy bills though which I think @I2C suggested in his reply hence there is no requirement to do so, loading 1 phase up and leaving 2 empty will cost exactly the same as balancing the loads, although like I said, it is good practice to do so.

 

[Pete999]

Totally agree, it was just the ambiguity of the wording that gave the impression it was a requirement hence I queried it but yes where possible having balance gives better scope for future additions of 3ph equipment, it won't save any money on energy bills though which I think @I2C suggested in his reply hence there is no requirement to do so, loading 1 phase up and leaving 2 empty will cost exactly the same as balancing the loads, although like I said, it is good practice to do so.

Would a heavily loaded SP on a TP&N installation incur any charges from the supplier for having PF problems, I'm not sure might be worth looking into.

 

[Darkwood]

Would a heavily loaded SP on a TP&N installation incur any charges from the supplier for having PF problems, I'm not sure might be worth looking into.

I have never seen it and tbh most installations are part of a bigger network and it would take a very big plant to cause big issues to the network as natural balancing occurs across local network distribution, the only issue I foresee would be the voltage drop on the loaded phase to the 2 unloaded phases, putting 3ph equipment on this may see issues due to the voltage variation across 1ph to the others, I have seen plants that have 200amps difference between phases and been running like that for years but yes, it can have consequences although unless you deliberately load only 1ph up and ignore the other 2 then phases tend to get some sort of balancing even though it may not be brilliant.

 

[Darkwood]

Just seen where I got 32amp from in regard to socket outlets and rcd protection, it's for mobile equipment for use outdoor so that 32A figure in my head was related to the same reg .. I'm not losing it then