Hey Everyone,
I've scoured the threads on this forum and many others but I still seem to end up confused when calculating amperage draw on 208v moving lights.
to keep the numbers simple in this example I will have 6 x 2000W fixtures on a standard splay. Phasing is as follows:
C1:XY
C2:XY
C3:XZ
C4:XZ
C5:YZ
C6:YZ
Now I can find the current draw of a light by dividing the wattage by the voltage: 2000w/ 208v = 10a (I'll round to 10 to make this simple)
Now I place the current draw of each phase out in a chart that the lights will be plugged into on a splay:
once I do this I add the total of the current draw of each phase and then divide it by the square root of 3 and that gives me 24a current draw on each phase. I've been told this is correct from a colleague. Though everything I've researched on this forum is leading me to multiply the total current draw on each leg instead of divide. That will leave me with 69a per leg (X, Y, and Z) it can't be that each leg is already drawing 69 amps with only 6 lights. ( 207a total) That's rightly absurd in my estimation. Or do I have it right by dividing that total of 69a across all 3 phases and each are sharing the load by 24amps?
If anyone can tell me where I'm going wrong and where I'm going right with this that would be greatly appreciated!
Thanks!
I've scoured the threads on this forum and many others but I still seem to end up confused when calculating amperage draw on 208v moving lights.
to keep the numbers simple in this example I will have 6 x 2000W fixtures on a standard splay. Phasing is as follows:
C1:XY
C2:XY
C3:XZ
C4:XZ
C5:YZ
C6:YZ
Now I can find the current draw of a light by dividing the wattage by the voltage: 2000w/ 208v = 10a (I'll round to 10 to make this simple)
Now I place the current draw of each phase out in a chart that the lights will be plugged into on a splay:
X | Y | Z | |
10 | 10 | ||
10 | 10 | ||
10 | 10 | ||
10 | 10 | ||
10 | 10 | ||
10 | 10 | ||
40 | 40 | 40 | Sum total |
24a | 24a | 24a | TOTAL |
once I do this I add the total of the current draw of each phase and then divide it by the square root of 3 and that gives me 24a current draw on each phase. I've been told this is correct from a colleague. Though everything I've researched on this forum is leading me to multiply the total current draw on each leg instead of divide. That will leave me with 69a per leg (X, Y, and Z) it can't be that each leg is already drawing 69 amps with only 6 lights. ( 207a total) That's rightly absurd in my estimation. Or do I have it right by dividing that total of 69a across all 3 phases and each are sharing the load by 24amps?
If anyone can tell me where I'm going wrong and where I'm going right with this that would be greatly appreciated!
Thanks!