Rockwell Automation Allen-Bradley PowerFlex 20P - Low or Incorrect Field Current

124 Rockwell Automation Publication 20P-TG002B-EN-P - February 2018
Appendix C Flow Charts
Low or Incorrect Field Current
Verify the value of
Par 351 [Field Current]
by using a DC current
clamp to measure the
DC motor eld current.
Verify that the value of
Par 280 [Nom Mtr
Fld Amps] matches the
rated eld current value
on the motor nameplate.
Is the voltage
measurement
correct?
No
Yes
Using an ohmmeter,
measure the resistance
across terminals LA-LB to
verify that the value
equals the equivalent
resistance set with
DIP switch S14.
Is the
resistance measurement
correct?
Replace the
eld board.
No
Yes
Verify that the drive rated
eld bridge current is
set correctly in Par 374
[Drv Fld Brdg Cur] and
DIP switch S14 is
congured to match.
Measure the eld current
signal at terminals LA-LB
located on the
control board. This value
should be equal to the
value of Par 374 [Drv Fld
Brdg Cur]. If these
values are equivalent,
the voltage across
terminals LA-LB should
be 1.66V DC.
Replace the
control board.