Rockwell Automation 7000 PowerFlex Medium Voltage AC Drive (B Frame) - Classic Control - Manual (Page 220)

Commissioning 4-61
7000 “B” Frame 7000-UM150I-EN-P – June 2013
Line Terminal Resistance Measurements
Measuring the resistance between the drive line cable terminals will
quickly identify if there is interwiring between the 0

, +20

, and -20

bridges in the isolation transformer.
2U
2V
2W
3W
3V
3U
4W
4V
4U 2U
2V
2W
3W
3V
3U
4W
4V
4U
There are low resistances between phases through a transformer
winding and a high resistance between transformer windings.
Therefore, the expected resistance measurements are listed in the
table below:
Terminal Measurement Points Expected Resistance
2U  2V  2W Approximately 0 Ω
3U  3V  3W Approximately 0 Ω
4U  4V  4W Approximately 0 Ω
#U  #V  #W Approximately ∞ Ω 
If the measurement results are not as described above, the interwiring
between the isolation transformer and drive needs to be re-inspected.