User`s manual

Error Reporting
GFK-1742A Appendix A Error Reporting A-15
A
Troubleshooting Digital Servo Alarms:
The guidelines below are intended to assist in isolating problems associated with various servo
alarms. If the items below do not fit the case or resolve the alarm, replace the servo amplifier, or
call GE Fanuc Hotline for support. The appropriate amplifier and motor, Maintenance Manual or
Description Manual, will include more detailed trouble shooting procedures.
HV (High-voltage) Alarm:
This alarm occurs if the high voltage DC level (DC LINK) is
abnormally high.
1. The AC voltage supplied to the amplifier may be higher than the rated input voltage. The
β
Series amplifier, three-phase supply voltage should be between 200 VAC to 240 VAC.
2. The external regeneration resistor may be wired incorrectly. Carefully check the connections
of the regeneration resistor to the amplifier. Check that the resistance of the regeneration
resistor is within 20% of the rated value. Replace the regeneration unit if the resistance is out
of tolerance.
3. The regeneration resistor may not be capable of dissipating excess generated voltage.
Review the calculations for selecting the regenerative discharge unit and replace with a
resistor of higher wattage rating as needed. Reducing acceleration values and position loop
gains (larger value
Position Loop Time Constant
) will additionally reduce regenerated
voltage levels.
LVDC (Low Voltage DC Link:
This alarm occurs if the high voltage DC level (DC LINK)
voltage is abnormally low.
1. The AC voltage supplied to the amplifier may be missing or lower in value than the rated
input voltage. The
β
Series amplifier, three-phase supply voltage should be between 200
VAC to 240 VAC. Verify that the proper level of AC voltage is supplied to the line input
(L1, L2 and L3) connections of the amplifier.
DCOH or DCSW (Regeneration Alarm):
The DCOH alarm occurs if the temperature of the
regeneration resistors is too high. The DCSW alarm indicates problems in the switching portion
of the regeneration circuitry.
1. If the external regeneration resistor is
not
used check that the temperature sensor input to the
amplifier is shorted or jumped. The
β
Series amplifier jumper T604 should be installed on
connector CX11-6.
2. The external regeneration resistor may be wired incorrectly. Carefully check the connections
of the regeneration resistor to the amplifier. Check that the resistance of the regeneration
resistor temperature sensor is near zero ohms at room temperature. Replace the regeneration
resistor if the temperature sensor indicates an open condition.
3. The regeneration resistor may not be capable of dissipating excess generated voltage.
Review the calculations for selecting the regenerative discharge unit and replace with a
resistor of higher wattage rating as needed. Reducing acceleration values and position loop
gains (larger value
Position Loop Time Constant
) will additionally reduce regenerated
voltage levels.
OH (Over-heat Alarm):
The temperature of the amplifier heat sink is too high or motor
temperature is excessive.
1. Ambient temperature may be too high, consider a cooling fan for the servomotor. GE Fanuc
supplies fan kits for most FANUC motors.