Rockwell Automation DC3RD Digital Regenerative DC Drive User Guide 1/4 - 2 HP, 115/230 VAC - Manual (Page 39)

IR COMP
The IR COMP trimpot setting determines the degree to
which motor speed is held constant as the motor load
changes. It is factory set for optimum motor regulation. See
Figure 8, page 40, for recommended IR COMP trimpot
settings.
To calibrate IR COMP (exact calibration):
1. With the motor rotating in the forward direction, set the
forward speed adjust potentiometer until the motor runs
at midspeed (for example, 900 RPM for an 1800 RPM
motor).
2. Load the motor armature to its full load armature
current rating. The motor should slow down.
3. While keeping the load on the motor, rotate the IR
COMP trimpot until the motor runs at the speed
measured in step 1.
Approximate calibration:
If the motor does not maintain set speed as the load
changes, gradually rotate the IR COMP trimpot CW. If the
motor oscillates (overcompensation), the IR COMP trimpot
may be set too high (CW). Turn the IR COMP trimpot
CCW to stabilize the motor speed.
31 Calibration
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