22
Calibration
IR COMPENSATION (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 6 on page 25 for recommended IR COMP trimpot
settings, or recalibrate using the following procedure:
1. Set the IR COMP trimpot to minimum (full CCW).
2. Rotate the speed adjust potentiometer until the motor runs at
midspeed without load (for example, 900 RPM for an 1800
RPM motor). A hand held tachometer may be used to
measure motor speed.
3. Load the motor armature to its full load armature current
rating.
4. While keeping the load on the motor, rotate the IR COMP
trimpot until the motor runs at the speed measured in step 2.
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.
5. Unload the motor.