3 Phase

[dcocks]

Hi
does any electric experts know how to take 240 single phase of a 3 phase outlet
i have been told that you can use 1 live and the neutral to get single phase is this right?
any advice welcome
Cheers david

 

[irondarren]

with 3 phase there are 3 wires, normally Red, yellow and blue. There is also a black wire (neutral). Take the black wire and any of the coloured wires and you have 240volt single phase. From what i remember from a 3 phase supply its is best to balance the phases when using 240volt. Ie if you have 3 machines drawing 2KW each, don't just connect up a 240v supply to one phase, connect one machine to each phase. Balance it out buy trying to keep the load on each phase on 240v similar.

 

[Robotstar5]

with 3 phase there are 3 wires, normally Red, yellow and blue. There is also a black wire (neutral).

Thanks to harmonisation with the EC you may have Brown, Black and Grey as 3 phase colours with Blue as the neutral so be careful as you could supply 415V to your 230V machine!

 

[Hitch]

One of the numbered ones, 1,2, or 3 and the one thats left

 

[dcocks]

i think our wires are all the same colour with live and neutral stamped on them well L1 L2and L3 so i would assume that the other one is the neutral
David

 

[dcocks]

Hitch
do we use the earth wire aswell
David

 

[piman]

Hello Dcocks,

yes we use the earth, connect to the metal body of whatever you are connecting to.

It is purely a safety connection.

Alec

 

[dcocks]

Hi all
Just had a look in our 3 phase sockets and we have 3 lives and a earth but no neutral. Not had a look in the socket isolater yet so it looks like getting 240 fron there is a not on?
Thanks david

 

[irondarren]

earth is neutral, well eventually the neutral goes to earth. It is possible to pull 240v from a single live and the earth, but possibly not recomended

 

[Drains]

Hi all
Just had a look in our 3 phase sockets and we have 3 lives and a earth but no neutral. Not had a look in the socket isolater yet so it looks like getting 240 fron there is a not on?
Thanks david

There will be a neutral somewhere... and you do have the option of bringing it in to the sockets, although you should then be re-wiring with new 5 core cable. You need to trace the line back to where there is a neutral and work from there.

Are your sockets 4 pin or 5 pin?

 

[dcocks]

Hi Simon
our plugs are 4 pin
David

 

[Drains]

So deffo no neutral then. Like I say, you'll have to hunt it out. Then you can take a 240v spur off it and one phase, as you know. Can't help you more than that i'm afraid.