Sockets on different phases

[Mark6098]

2 sockets on dado trunking within half a metre of each other, would you agree on warning notices for potential 400v?

 

[Engineer54]

Can't be fussed reading all your responses but to the OP. It's not a reg but for good measure if I can touch both, I will re arrange the DB if possible or blank one off.

I Think for good measure, you need to read post #33, ....As neither of you're measures are either required or needed!!!

 

[Darkwood]

I can see it now, someone who is not competent to do so removing both socket covers and reaching between them and been killed!!!

No mention that 230v to earth can do it just as good if all on same phase ...as i said competence will ensure no issues of safety if non competent person enters the scenario then Darwins law is a useful universal law to which i agree with.

 

[Engineer54]

I think some of these people need to visit some industrial or large commercial premises to see for themselves, that it's not only common, but is standard practice!!

In this instance (OP's situation) it's an office installation, and would be a perfectly acceptable and normal method of wiring large amounts of socket outlets across a 3 phase supply....

 

[Rockingit]

Come to a large theatre or onto a live stage and you'll find ph<>ph in all manner of combinations all over the shop. Lighting bars will often have socket outlets as 1,2,3,1,2,3,1,2,3,1,2,3... and so on, simply as they are hard wired back to 3ph dimmers!

 

[Lucien Nunes]

the only issue I see is the average joe blogs seeing 400v next to a socket and worrying about using it.

Agreed also. I would not label sockets now that there is no requirement to do so. Lots of so-called electricians don't understand where the 400V comes from so the average user won't have a clue. Labels that don't convey useful information are a menace and cause confusion. I saw a similar situation in an office where a 6-way plastic gridswitch on a new install had a 'Danger 400V' label stuck on the dado trunking next to it. The office staff were pushing the switches with a plastic rule because no-one knew what the danger actually was!

Stage lighting is a bit of an exception because the sockets are normally intended for use by instructed persons. We used to do the Trafolyte channel labels in the appropriate colours but you can't see the difference with harmonised colours so use the numbers now.

 

[Engineer54]

Agreed also. I would not label sockets now that there is no requirement to do so. Lots of so-called electricians don't understand where the 400V comes from so the average user won't have a clue. Labels that don't convey useful information are a menace and cause confusion. I saw a similar situation in an office where a 6-way plastic gridswitch on a new install had a 'Danger 400V' label stuck on the dado trunking next to it. The office staff were pushing the switches with a plastic rule because no-one knew what the danger actually was!

Stage lighting is a bit of an exception because the sockets are normally intended for use by instructed persons. We used to do the Trafolyte channel labels in the appropriate colours but you can't see the difference with harmonised colours so use the numbers now.

We still do, on some of our installation areas, but for ckt identification purposes, not for any form of 400V warning.... They seem to have labels for just about every situation now in the UK, most of them totally pointless and at worst (as you say) confusing!!

 

[Hawkmoon]

I think some of these people need to visit some industrial or large commercial premises to see for themselves, that it's not only common, but is standard practice!!

In this instance (OP's situation) it's an office installation, and would be a perfectly acceptable and normal method of wiring large amounts of socket outlets across a 3 phase supply....

Yes but what I was referring to as being less common is having to install closer than 2M between in an office/IT room (op) - so requiring the label (pre 17th am 1)

 

[Engineer54]

Doesn't matter mate, they can be next to each other (and often are), compliance with safe isolation practices, will always negate any perceived or real risks....

 

[Hawkmoon]

Doesn't matter mate, they can be next to each other (and often are), compliance with safe isolation practices, will always negate any perceived or real risks....

Fully agree - never argued anything different other than how common they are closely positioned in the OP type install - but we all have differing experiences

 

[Engineer54]

Fully agree - never argued anything different other than how common they are closely positioned in the OP type install - but we all have differing experiences

It's been a long day today and may have missed you're point. lol!!

 

[Guest111]

The worst one I ever came across was in a training centre for electricians,a single metalclad socket below a DB,connected to this by a coupler and 2 bushes was another single socket,now one was fed off red phase and one off yellow phase,with both sets of feeds going through the first box.I commented on it to one of the instructors who replied "it'll be ok one of us fitted it so we know about the way it's done"

 

[Les Macaulay]

why would you need warning signs?? for what?

In the event of simultaneous line to earth faults on appliances using these socket outlets, the metalwork on both would rise to mains voltage until the protective device for each has operated to clear the faults. This is highly unlikely, but is possible. If it did occur, shock voltage when the metalwork of both were to be touched simultaneously would be 400V, not funny.

 

[DPG]

In the event of simultaneous line to earth faults on appliances using these socket outlets, the metalwork on both would rise to mains voltage until the protective device for each has operated to clear the faults. This is highly unlikely, but is possible. If it did occur, shock voltage when the metalwork of both were to be touched simultaneously would be 400V, not funny.

Note, thread is 8 years old.

 

[littlespark]

Note, thread is 8 years old.

I’ve got socks older than that!

 

[pc1966]

I’ve got socks older than that!

Not a problem, so long as they have been washed frequently!

 

[snowhead]

I’ve got socks older than that!

Not a problem, so long as they have been washed frequently!

And you don't mount them in such a way that you can touch both at the same time,, It may be shocking.

 

[i=p/u]

Requires a sticker if 2 phases at one accessory I.e light switch bank

 

[James]

Requires a sticker if 2 phases at one accessory I.e light switch bank

What reg no. is that?

 

[Mike Johnson]

If I have two phase's adjacent to each other I put a L1, L2 or L3 on the socket just to inform whoever that its there, no requirement for it, but I just do it anyway.

 

[i=p/u]

What reg no. is that?

514.10.1 maybe