Rockwell Automation 1397 DC Drive Firmware 2.xx - Manual (Page 106)

4–34 Start–Up and Adjustment
Publication 1397-5.0 — June, 2001
Pulse Encoder Polarity Checks (Regenerative Drives Only)
!
ATTENTION: Prior to running polarity checks, you
must provide a hardwired maintained external operator
accessible coast/stop pushbutton at regulator board
terminals 7 and 8 to disable the machine in case of
improper operation. Uncontrolled machine operation
can result if this is not done. Failure to observe this
precaution could result in severe bodily injury or loss
of life.
1. Verify that [Feedback Type] (P. 039) is set to Pulse Tach for
pulse tachometer (encoder).
2. Verify that the pulse encoder is properly terminated by
monitoring [Encoder Fdbk] (P. 189) when the motor is rotated
in the same direction as it was in Step 6 of the Motor and
Feedback Polarity checks.
3. The value in [Encoder Fdbk] (P. 189) should be positive
(magnitude is unimportant).
4. If the value observed is negative, remove power from the Drive
and reverse the pulse encoder connections terminated at the pulse
encoder interface board. This interface board is located behind
the regulator board, inside the regulator carrier.
Reverse the polarity of only one channel, i.e B and B NOT
located at terminals 75 and 76 of the pulse encoder interface
board.
5. Proceed to Verification of Drive Calibration.