In Europe the standard voltage is 230V (Phase to Neutral)
I don't know the system in USA but, I'm just wondering...
As I remember from the times that I was mechanic on the B-707 / B-747, the generators were specified as "115/200V - 3 Phase - 90 KVA" when;
Phase to Neutral = 115V
Phase to Phase = 200V
That's because the generator Phases are at 120° one to the other and the "Picks" are never at 180° opposite one to the other.
As I remember, the calculation of the "Phase to Phase" Voltage is (if the "hard drive" is still working properly ...)
Square root of 3 multiplied by the "Phase to neutral" Voltage or
sin 120° x 230V (Phase to Phase Voltage);
1.732 x 115 = 199.186 V or
0.866 x 230 = 199.186 V
So the "Phase to Phase" voltage of 120V should be;
1.732 x 120 = 207.85 (or 208V when rounded)
It looks to me that if you want to operate an 230V motor - the motor runs on lower than the specified voltage that, as we all know, is a "killer" for any electric motor...
So, how do you get 230 or 240V in USA (probably, I'm missing something...)
Many thanks
niki
I don't know the system in USA but, I'm just wondering...
As I remember from the times that I was mechanic on the B-707 / B-747, the generators were specified as "115/200V - 3 Phase - 90 KVA" when;
Phase to Neutral = 115V
Phase to Phase = 200V
That's because the generator Phases are at 120° one to the other and the "Picks" are never at 180° opposite one to the other.
As I remember, the calculation of the "Phase to Phase" Voltage is (if the "hard drive" is still working properly ...)
Square root of 3 multiplied by the "Phase to neutral" Voltage or
sin 120° x 230V (Phase to Phase Voltage);
1.732 x 115 = 199.186 V or
0.866 x 230 = 199.186 V
So the "Phase to Phase" voltage of 120V should be;
1.732 x 120 = 207.85 (or 208V when rounded)
It looks to me that if you want to operate an 230V motor - the motor runs on lower than the specified voltage that, as we all know, is a "killer" for any electric motor...
So, how do you get 230 or 240V in USA (probably, I'm missing something...)
Many thanks
niki
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