Specifications

63230-507-201A1 Power Meter 750

03/2007 Appendix C—Instrument Transformer Wiring: Troubleshooting Guide

Table C– 13:Section IV—Case E

Symptoms: 4-Wire Possible Causes

• kW = near 0

• kVA = near 0

• 3-phase average power factor flip-flopping lead and lag

• Voltages, currents, and kVA are normal

• Two CT secondary leads are swapped (A-phase on B-phase terminal, for

example)

• Two PT secondary leads are swapped (A-phase on B-phase terminal, for

example)

NOTE: In either case, the phase input that is not swapped will read normal lagging power

factor.

Table C– 14:Section IV—Case F

Symptoms: 4-Wire Possible Causes

• kW = negative and less than kVAR

• KVAR = negative and close to value expected for kW

• kVA = expected value

• Power factor low and leading

• Voltages and currents are normal

• All three PT lead connections “rotated” counterclockwise: A-phase wire on

C-phase terminal, B-phase wire on A-phase terminal, C-phase wire on B-

phase terminal.

• All three CT lead connections “rotated” clockwise: A-phase wire on B-phase

terminal, B-phase wire on C-phase terminal, C-phase wire on A-phase

terminal.

Table C– 15:Section IV—Case G

Symptoms: 4-Wire Possible Causes

• kW = negative and less than kVAR

• kVAR = positive and close to the value for kW

NOTE: looks like kW and kVAR swapped places

•

kVA = expected value

• Power factor low and lagging

• Voltages and currents are normal

• All three PT lead connections “rotated” clockwise: A-phase wire on B-phase

terminal, B-phase wire on C-phase terminal, C-phase wire on A-phase

terminal.

• All three CT lead connections “rotated” counterclockwise: A-phase wire on

C-phase terminal, B-phase wire on A-phase terminal, C-phase wire on B-

phase terminal.