6.4.2 Y Axis Home Position Error
Monitor Timing: At time of Y axis home position sensing
Monitor Method: The photo interrupter shades the light of Y-axis drive mechanism.
CA-500’s Action: Emergency stop
(1) Probable Cause
1. Drive mechanism operation is obstructed.
2. Loosened pulley of motor
3. Failure of PCB No. 2134
4. Defective light shield
5. Flaw on shaft
6. Failure of slider
7. Failure of PCB No. 9260
8. Failure of X axis wiring cord
9. Failure of PCB No. 6362
10. Failure of Y axis motor assembly
11. Failure of PCB No. 4086
(2) Confirmation by the Operator
1. Remove the obstruction in Y-axis drive mechanism.
2. Turn off the power supply, then turn it on again.
(3) Confirmation by Service Engineer
1. Retighten the screw of the pulley of motor.
2. If home position cannot be detected even when the drive mechanism is operated:
a) Check whether the light shield is defective or not.
Suspect Part Test Points Expected Value
Position sensor CN1 (PCB No. 2134) pin 19 and pin 20 (GND) 5 V Æ 0 V when the sensor is
shielded
CN1 (PCB No. 9260) pin 19 and pin 20 (GND) 5 V Æ 0 V when the sensor is
shielded
CN105 (PCB No. 6362) pin 6 and pin 14 (GND) 5 V Æ 0 V when the sensor is
shielded
3. When the motor does not operate:
a) Any of motor, PCB No. 2134, X-axis wiring cord (18 wire cable), or PCB No. 4086 is faulty.
Replace and confirm.
b) Turn the pulley by hand. If it does not move, the motor or drive mechanism is faulty.
4. Failure of the drive mechanism
a) Check for flaws on the shaft.
b) If the shaft is free from flaws, the problem is in the bushing.
CA-500 Series S/M 6-9 Revised December 2001 8
To Next Page
Loading...
