13A sockets different phases

[timhoward]

Hi
On Friday I found 2 x 13A double sockets about 30 cm apart in an office. One of them was on same circuit as all other sockets in same room. The 2nd one had been added, and drilled through from the adjacent office. The circuits are on different phases. Common sense dictates that a 400v potential difference is dangerous between them and I blanked the offending one off.
It's created an argument as this has inconvenienced the occupants. It would be very simple to add a spur off the original one and I've offered to do this, however argument is along the lines "nothing wrong with it, been like that for years, show me in writing why that isn't allowed. It didn't come up on the last inspection.". (Red/Black wires so been there a long time.)

Being honest - I'm struggling to point to a reg that explicitly talks about this. Assistance welcomed.
Best I've found at moment is section 314 "Division of Installation" with point i) being "avoid danger". As occupier is not accepting danger....this doesn't get me far.
Thanks in advance for any help.

 

[westward10]

There is nothing to say socket outlets in close proximity cannot be on different phases. Reinstate the socket outlet.

 

[timhoward]

There is nothing to say socket outlets in close proximity cannot be on different phases. Reinstate the socket outlet.

Thank you. Good to know. Taking on board that it is permitted....and I will sort it...

This does nonetheless feel slightly wrong, when you design a circuit for ADS and a 0.4s disconnection time, you are assuming U0 is up to 230v for that circuit. I'll admit that I can't readily think of a set of faults that isn't extremely unlikely, like two class 1 items both with broken earth in plug, both faulty, and both on different phases, but it feels like this design is opening up the outside possibility of 400v flowing which would halve the required disconnection time on TN (table 41.1).

Maybe this is all so unlikely I'm over thinking it, I just thought that it's best avoided if possible, and it's very possible in this case. Thanks again - every day a school day!

 

[Julie.]

There is no regulation dictating any separation between outlets on different phases, so there is absolutely nothing wrong there.

 

[westward10]

Thank you. Good to know. Taking on board that it is permitted....and I will sort it...

This does nonetheless feel slightly wrong, when you design a circuit for ADS and a 0.4s disconnection time, you are assuming U0 is up to 230v for that circuit. I'll admit that I can't readily think of a set of faults that isn't extremely unlikely, like two class 1 items both with broken earth in plug, both faulty, and both on different phases, but it feels like this design is opening up the outside possibility of 400v flowing which would halve the required disconnection time on TN (table 41.1).

Maybe this is all so unlikely I'm over thinking it, I just thought that it's best avoided if possible, and it's very possible in this case. Thanks again - every day a school day!

ADS is based on the nominal voltage, 230 so the fact these outlets may have 400v between their line terminals is not relevant. Several Regulation editions back it would have been a requirement to put in place a warning notice but this is no longer the case.

 

[andyb]

If you wouldn't normally expect 400v between the sockets I'd recommend a sign or label fixed between them. Though as already said, there's no reg prohibiting it.

 

[Rockingit]

In my world, it’s an every day occurrence to have alternating socket outlets L1, L2, L3 and be only inches from each other. (Theatre lighting bars)

 

[timhoward]

If you wouldn't normally expect 400v between the sockets I'd recommend a sign or label fixed between them. Though as already said, there's no reg prohibiting it.

I've just had a very gracious email back from them (after I admitted I was wrong and I'd put it back) and they are now saying that I'm not the first to question this and to make future maintenance easier and safer can I in fact just sort it. Which I'll gladly do FOC in the circumstances
Thanks all.

 

[westward10]

I've just had a very gracious email back from them (after I admitted I was wrong and I'd put it back) and they are now saying that I'm not the first to question this and to make future maintenance easier and safer can I in fact just sort it. Which I'll gladly do FOC in the circumstances
Thanks all.

Good for you.

 

[telectrix]

I've just had a very gracious email back from them (after I admitted I was wrong and I'd put it back) and they are now saying that I'm not the first to question this and to make future maintenance easier and safer can I in fact just sort it. Which I'll gladly do FOC in the circumstances
Thanks all.

takes courage to admit you were wrong. hat off to you.

 

[James]

I've just had a very gracious email back from them (after I admitted I was wrong and I'd put it back) and they are now saying that I'm not the first to question this and to make future maintenance easier and safer can I in fact just sort it. Which I'll gladly do FOC in the circumstances
Thanks all.

You have a customer for life there.

you can do 20 jobs right first time and not be noticed much for it.

1 job with a problem, even if its your fault will Make you stand out and shine if it is handled correctly.

honesty is the best policy as they say, as long as you are not "the accused" in a court room!!