3x230

[Gardner]

When you say 'system' is the building supply 2 phases as you describe without a neutral or is this just a final circuit.

Either way the answer is yes in most places on the planet (including Derbyshire....wherever it may be), you'd need every point of consumption including light fittings to be supplied by a double pole switch.

I think England is in Derbyshire and Derbyshire is part of the UK, but I might be wrong .

Building supply and final circuit. 4 conductors (3 phases and a PE)

What part of the regs require 2 pole switches for lights?

 

[Lucien Nunes]

Yes, lights would need DP switching otherwise the lampholder would still be live w.r.t. earth with the switch off.

 

[Gardner]

Yes, lights would need DP switching otherwise the lampholder would still be live w.r.t. earth with the switch off.

But how do lamp sockets work on devices with a schuko plug?

 

[Lucien Nunes]

You pull the plug out! BTW, the very reason that Schuko isn't polarised, is that this method of supply was once used in Germany, and there was no advantage polarising the connector when both sides were lines. But that was phased out (see what I did there?) in favour of ordinary star 230/400.

 

[Gardner]

You pull the plug out! BTW, the very reason that Schuko isn't polarised, is that this method of supply was once used in Germany, and there was no advantage polarising the connector when both sides were lines. But that was phased out (see what I did there?) in favour of ordinary star 230/400.

But if its ok for a table lamp, why would it be different for a light fitting? Unless the socket is designed to denergize the screw shell when removing the bulb?

Double pole switches would be easy, but 2 way switches would be a challenge.

 

[Lucien Nunes]

The wiring of buildings comes under a different set of regulations than the construction of portable appliances. For a start, BS7671 is specific to the UK (although it references and relies on many harmonised standards) whereas appliances in the EU are generally applicable anywhere.

Can someone quote the OP the reg number of '...must break all line conductors...'?

 

[Gardner]

The wiring of buildings comes under a different set of regulations than the construction of portable appliances. For a start, BS7671 is specific to the UK (although it references and relies on many harmonised standards) whereas appliances in the EU are generally applicable anywhere.

Can someone quote the OP the reg number of '...must break all line conductors...'?

Thanks

Id argue the same risks with a lamp also apply to a light fitting.

 

[davesparks]

But if its ok for a table lamp, why would it be different for a light fitting? Unless the socket is designed to denergize the screw shell when removing the bulb?

Double pole switches would be easy, but 2 way switches would be a challenge.

You couldn't use screw lampholders on this systwm you are proposing as the regulations require that line only be connected to the centre pin and neutral to the outer contact. You would have to use BC for GLS lamps

 

[Gardner]

You couldn't use screw lampholders on this systwm you are proposing as the regulations require that line only be connected to the centre pin and neutral to the outer contact. You would have to use BC for GLS lamps

How do table lamps get away with Schuko plugs though? Id imagine some safety mechanism is used on those sockets.

 

[ian.settle1]

How do table lamps get away with Schuko plugs though? Id imagine some safety mechanism is used on those sockets.

Why don't you ask an earlier question as to where you are from so people can answer your questions correctly?

 

[Pete999]

Am I missing something? Where or how are you measuring 230v between two lines?

Me as well

 

[Lucien Nunes]

I think it's a hypothetical question, I didn't get the impression that the OP was actually measuring this voltage. But systems that work in this way do exist, shipboard delta supply was one I mentioned. I also have a 20kVA generating set of the same voltage, 133V L-N, 230V L-L, but it's corner-grounded so the neutral star point is of no use and isn't brought out to the panel. You can have two supplies of 230V sharing what looks like a neutral, but when you measure between them, instead of 400V, you get 230V again because they're 60° apart not 120°.

 

[davesparks]

How do table lamps get away with Schuko plugs though? Id imagine some safety mechanism is used on those sockets.

Schuko plugs aren't used in this country so there is no point attempting to apply our regs to them

 

[snowhead]

Thanks

Id argue the same risks with a lamp also apply to a light fitting.

For changing a lamp a D.P switch in a fixed system provides isolation of both poles.
For changing a lamp with a Schuko plug, pulling the plug provides D.P isolation

 

[Gardner]

I think it's a hypothetical question, I didn't get the impression that the OP was actually measuring this voltage. But systems that work in this way do exist, shipboard delta supply was one I mentioned. I also have a 20kVA generating set of the same voltage, 133V L-N, 230V L-L, but it's corner-grounded so the neutral star point is of no use and isn't brought out to the panel. You can have two supplies of 230V sharing what looks like a neutral, but when you measure between them, instead of 400V, you get 230V again because they're 60° apart not 120°.

Its a center grounded wye made with 135 volt wingdings to give 230 volts L-L. It is indeed TN rather then IT.

Schuko plugs aren't used in this country so there is no point attempting to apply our regs to them

Id imagine the interior wiring would still be applicable, no?