Baldor UM Series, Installation & Operating Manual

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4-2 Adjustments & Start-Up MN1213
Start–Up Velocity Mode
(Power On)
1. Decouple all loads from the motors.
2. Disconnect all axes except the first (axis 1)
3. Switch on the Logic and Fan AC power input.
4. Observe that the fan starts and three of the green LED’s on the logic
power supply (+ 15V, – 15V and AC) are ON.
5. Apply the AC input power to the external isolation transformer and verify
that the fourth green LED labeled ”BUS” is ON.
6. Observe that the servo motor does not rotate. If the servo motor runs up
to a high speed at an uncontrolled rate, reverse the tachometer or
armature leads.
7. Apply a signal step input command between 0 and 10VDC at terminals 1
and 4 on the signal input connector. A 5VDC input voltage is
recommended.
8. Slowly rotate the (S) Signal pot 4 turns clockwise, observing that the
motor shaft rotates at a reasonably controlled rate. Be careful with this
step because if a tachometer is miswired, the motor can runaway.
9. Slowly rotate the (C) Current pot 4 turns clockwise, observing that the
motor shaft speed may increase and stabilize.
10. If the motor shaft rotates in the wrong direction for a given polarity input
voltage, reverse both the tachometer wires and the red and black
armature wires at the terminal block.
11. Verify that the Left and Right limit switches properly inhibit the axis travel
in the direction defined.
12. Slowly rotate the (S) pot clockwise to increase the motor shaft speed to
full speed.
13. If a high output voltage tachometer is used, it may be necessary to turn
the (T) pot a few turns counterclockwise to achieve the desired speed.
14. Slowly rotate the (C) pot to the fully clockwise position if the servo
control’s peak current is less than the rated peak current of the motor. If
the peak motor current is less than that of the servo control, a reduced
current must be maintained.
15. Slowly turn the (R) pot clockwise until the axis becomes unstable and
then turn the pot back one turn counterclockwise. This adjustment is
best done with a step input command (refer Figure 4-2 for typical
responses).
16. If the motor shaft rotates with the signal input voltage at zero, slowly
adjust the (B) pot to eliminate any motor shaft rotation.
17. If the motor shaft overshoots when stopping, slowly adjust the (T) pot
counterclockwise, be careful not to turn it to fully counterclockwise. Fully
counterclockwise adjustment of the (T) pot may cause the speed of the
motor shaft to become uncontrollable.
18. The (S) pot can now be adjusted to optimize the maximum response for
the given signal input voltage range.
19. Turn off AC input power to the external isolation transformer and AC
input power to the Logic & Fan input.