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3x230

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Is such a system (230 volt L-L) legal under BS7671 or IEC 60364? Do I need double pole switches for light fittings?
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 :).
 
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Since 133V isn't a normal supply voltage, SP loads would all have to be connected L-L and for practical purposes it would be used as a delta supply. Whilst delta power is common for certain applications, e.g. shipboard, it can make things a lot harder. All switching and OCP must be DP, so you can't use 13A plugs for example.

Illegal - no, but not terribly useful for most applications and a general purpose electrical installation fed that way might be considered unfit for purpose.
 
Since 133V isn't a normal supply voltage, SP loads would all have to be connected L-L and for practical purposes it would be used as a delta supply. Whilst delta power is common for certain applications, e.g. shipboard, it can make things a lot harder. All switching and OCP must be DP, so you can't use 13A plugs for example.

All loads are indeed connected L-L with 2 pole MCBs used on all circuits.

The switching I am unsure about. Would lights still need DP switching?

Illegal - no, but not terribly useful for most applications and a general purpose electrical installation fed that way might be considered unfit for purpose.

Sounds like a lot of draw backs. Is switching on of them?
 
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?
 
Yes, lights would need DP switching otherwise the lampholder would still be live w.r.t. earth with the switch off.
 
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.
 
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.
 
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...'?
 
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.
 
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
 
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.
 
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°.
 
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.
138,240Y.jpg

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?
 

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