# how to convert 3 phase voltage to a magnitude???

Discussion in 'The Projects Forum' started by iceman11`, Oct 17, 2008.

1. ### iceman11` Thread Starter Active Member

May 4, 2007
39
0
good day all, this is a simple question, but i jst cant find the answer to it : if i have a 3 phase line, but i wish to extract a single magnitude THAT IS EQUIVALENT to the 3 phase voltages how to i do that??

i know that there is some formula to do this? but i cant find it??

it is basically an amplitude calculator for all three line phase/line voltages

thanks

2. ### Externet AAC Fanatic!

Nov 29, 2005
781
58
If the voltages of the 3 phases are identically divided to a level that can be handled by a summer circuit, that would yield a proportional value. (But it will not reveal which one is the weakest nor the strongest phase)
(Like a microphone mixer circuit)
Miguel

3. ### SgtWookie Expert

Jul 17, 2007
22,183
1,729
AVERAGE of:
Potential A times sine (0 degrees)
Potential B times sine (120 degrees)
Potential C times sine (240 degrees)

What do you get?

If life is perfect, zero volts. However, life is seldom perfect.

4. ### iceman11` Thread Starter Active Member

May 4, 2007
39
0

hey, thanks,

but wudnt this mean that the magnitude contributed by the "phase A line" will always be 0, since sine 0 deg is 0...

this means that this wud contribute nothing to the overall magnitude...which is obviously not true

5. ### scubasteve_911 Senior Member

Dec 27, 2007
1,202
1
The average of any time-harmonic signal is zero, but not true for the products.

Steve

6. ### raybo Member

Oct 18, 2008
22
0
add diodes to each phase so you get rectify DC that is something that you can measure for sure . loose a line you will know. simple .