2330 - Unit 203

[Billy Ashton]

Hi guys i got a test coming up and come up with a question i have no clue how to work out.

If a line voltage in a 3 phase star connected system is 660v, what is the phase voltage?

Could anyone explain how this is worked out please?

Thanks Billy

 

[Andyr86]

Hi guys i got a test coming up and come up with a question i have no clue how to work out.

If a line voltage in a 3 phase star connected system is 660v, what is the phase voltage?

Could anyone explain how this is worked out please?

Thanks Billy

If I remember correctly you multiply square root of 3 (1.73) by Line Voltage. So 230 * 1.73 = 400.

In your example it will be will be 660 * 1.73 = 1141

 

[xcsx]

i think VL=sqroot of 3*VP so Vp=660/1.73= 381.05 volt

 

[dichroic]

Hi guys i got a test coming up and come up with a question i have no clue how to work out.

If a line voltage in a 3 phase star connected system is 660v, what is the phase voltage?

Could anyone explain how this is worked out please?

Thanks Billy

Your line voltage is your voltage between any two lines.........so 400v is measured between L1 and L2, L1 and L3 and L2 and L3. Your phase voltage is the voltage measured between any one line and your neutral...........L1 and N, L2 and N and L3 and N giving 230 volts.

so if you divide your line voltage in the UK by the square root of 3 (1.732) than you get your phase voltage.

So 400/1.732 = 230 volts.

 

[Andyr86]

i think VL=sqroot of 3*VP so Vp=660/1.73= 381.05 volt

This is correct, apologies. Had a blonde moment.