The following procedure should be used to adjust the Speed Gain Trimpot:
4
1)
Set the motor speed to 5-10% of maximum speed.
2) Apply a load to the motor and observe if the speed
increases or decreases.
3)
Remove the load.
4)
If speed increases under load, turn the trimpot counter-
clockwise.
If speed decreases under load, turn the trimpot
clockwise.
5) Repeat steps 2 through 4 until there is no observable
change in speed when load is applied or removed.
Note: if the motor oscillates when step 1 is attempted, turn the
trimpot counter-clockwise until the motor runs smoothly;
then proceed with steps 2-5.
(3) MOUNTING PLATE
The CN0121A is a linear amplifier. As a consequence it may dissipate considerable heat
while running large motors at low speed under heavy load. This heat may cause damaging
temperatures in the CN0121A. For this reason it is extremely important to properly heat sink
the drive.
Mount the CN0121A on a finned aluminum heat sink using thermal compound between the
CN0121A and the heat sink. If needed, use a fan to force air over the heat sink. Monitor the
case temperature of the CN0121A under the worst case motor load conditions. Do not let the
case temperature exceed 70
°
C (158
°
F).
