electrocuted
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how to calculate power( wattage) on 3 phase? just out of interest
how to calculate power( wattage) on 3 phase
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johninlondon1
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multiply voltage times amps times square root of 3
Hi, Just thought i would expand on that a bit.
It would be; Line voltage [400v] x the current [in one phase] x square root of three [1.732]
All this assumes a "balanced load" I.E. all three phases are carrying the same current.
OR
Phase voltage [230v] x current [in one phase] x 3
If you did it this way, i am not sure of the effect of an unbalanced load, although i am sure other forum members will be able to assist you with this [bit beyond me!]
Anyway, the answer would be in KW.
If you wanted KVA you would have to multiply the result by [PF x Efficiency]
john..
It would be; Line voltage [400v] x the current [in one phase] x square root of three [1.732]
All this assumes a "balanced load" I.E. all three phases are carrying the same current.
OR
Phase voltage [230v] x current [in one phase] x 3
If you did it this way, i am not sure of the effect of an unbalanced load, although i am sure other forum members will be able to assist you with this [bit beyond me!]
Anyway, the answer would be in KW.
If you wanted KVA you would have to multiply the result by [PF x Efficiency]
john..
john,
It would actually be in kW, or kVA, there is a subtle but VERY important difference!
It would actually be in kW, or kVA, there is a subtle but VERY important difference!
Hi Sidewinder, that is what i said, [i think]
"Anyway, the answer would be in KW.
If you wanted KVA you would have to multiply the result by [PF x Efficiency]"
Well, ok, i should have left out the bit about efficiency!
john..
"Anyway, the answer would be in KW.
If you wanted KVA you would have to multiply the result by [PF x Efficiency]"
Well, ok, i should have left out the bit about efficiency!
john..
Apprentice, its the letters, kW is not the same as KW,
Likewise, kVA is not KVA , there is difference , just the same as r1 or R1.
That is what Sidewinder means,I think.
Likewise, kVA is not KVA , there is difference , just the same as r1 or R1.
That is what Sidewinder means,I think.
You beat me to it Steps!
Not often that happens, 
Hi all!
I think what you mean is, that as i was referring to quantities measured in "thousands" [of watts] the correct prefix would [should] have been a lower case "k" [to denote "kilo" as in 1000] and not an upper case "K" that denotes a different quantity!! [1024]
Sort of [but not quite] along the same lines as mW are most very certainly not the same as MW!!!!!!
I have to say, i think this forum is brilliant!! Best one by far!!
John..
I think what you mean is, that as i was referring to quantities measured in "thousands" [of watts] the correct prefix would [should] have been a lower case "k" [to denote "kilo" as in 1000] and not an upper case "K" that denotes a different quantity!! [1024]
Sort of [but not quite] along the same lines as mW are most very certainly not the same as MW!!!!!!
I have to say, i think this forum is brilliant!! Best one by far!!
John..
Or K for Kelvin!
However you are correct!
Your mW/MW example is a very good one as to why the case is important.
However you are correct!
Your mW/MW example is a very good one as to why the case is important.
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