score 10
represents the worst case and should not used!
P-coil without PAW
Older coils may not equipped with power auxiliary winding. The same nominal
value 500 used for the P-coil's normal PAW should used for the conversion ratio for
the secondary side.
UNE_3
U0d
IS
ICI_3
UNE_2
PAW
Figure 133: Possible measurement points the P-coil with PAW
The below list possible combinations and their score:
Combination the
measurement
points:
Usual measurement accuracy Score*)
ICI_3 UNE_2
UNE3
IS
ICI3 UNE2 ±10% 5
ICI3 UNE3 ±3% 3
ICI3 U0d ±3% 3
IS UNE2 ±10% ±3% Bad condition for 8
IS UNE3 ±3% ±3% Bad condition for 7
IS U0d ±3% ±3% Bad condition for 7
*) score represents the best solution record the measured values.
In this case, single-phase transformer can used and connected parallel the P-coil's
main winding.
The short-circuit impedance should small possible.Page 196 Commissioning current injection
We take care it.
.
Requirements for the features the single-phase transformer
The transformer's output can set for the secondary side
