GE 845 Instruction Manual page 457

CHAPTER 6: METERING
845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
Winding 1 load (W1 Load (% of rated)) 0.0 %
Range: 0.0 to 100.0 %
Winding 1 average phase current (W1 Average Ph Current) 0.000 A
Range: 0.000 to 120000.000 A
Winding 1 harmonic derating factor (W1 Harm Derate Factor) 1.00
Range: 0.00 to 1.00
Winding 2 load (W2 Load (% of rated)) 0.0 %
Range: 0.0 to 100.0 %
Winding 2 average phase current (W2 Average Ph Current) 0.000 A
Range: 0.000 to 120000.000 A
Winding 2 harmonic derating factor (W2 Harm Derate Factor) 1.00
Range: 0.00 to 1.00
Winding 3 load (W3 Load (% of rated)) 0.0 %
Range: 0.0 to 100.0 %
Winding 3 average phase current (W3 Average Ph Current) 0.000 A
Range: 0.000 to 120000.000 A
Winding 3 harmonic derating factor (W3 Harm Derate Factor) 1.00
Range: 0.00 to 1.00
For a two winding transformer the winding load and winding average phase current are
calculated as:
W(1/2) Load (% of rated) = √3 x I
Where:
I = (I + I + I )/3 is the actual average phase current (W(1/2) Average Ph Current) for the
avg a b c
corresponding winding.
I , I , I are magnitudes of the corresponding actual phase currents of the winding.
a b c
V is the rated phase to phase nameplate voltage for the corresponding winding.
rated
S is the rated nameplate apparent power for the transformer.
rated
For three winding transformer the winding load and winding average phase current are
calculated as:
W(1/2/3) Load (% of rated) = √3 x I
Where:
I = (I + I + I )/3 is the actual average phase current (W(1/2/3) Average Ph Current) for
avg a b c
the corresponding winding.
I , I , I are magnitudes of the corresponding actual phase currents of the winding.
a b c
V is the rated phase to phase nameplate voltage for the corresponding winding.
rated
S is the rated nameplate apparent power for the transformer.
rated
(1/2) x V (1/2) x 100% / S
avg rated
(1/2/3) x V (1/2/3) x 100% / S
avg rated
TRANSFORMER
rated
(1/2/3)
Wrated
6–5