Haas NGC Alarm 102 SERVOS TURNED OFF after E-stop, what to check?
I'm getting Alarm 102 SERVOS TURNED OFF on my Haas NGC mill. It happens right after I release an E-stop and try to reset the machine. What should I be checking first?
Alarm 102 SERVOS TURNED OFF on a Haas Next Generation Control (NGC) indicates that the servo motors are currently off. This is a state, not a root cause, and typically occurs after power-on, an emergency stop, or another alarm that removes servo power. To clear it, you usually need to address the underlying cause and then press RESET.
Likely causes and checks
1Emergency stop pressed
- Points to it
- The most common reason for servos to be turned off after an E-stop is that the E-stop condition is still active or has not been properly reset.
- Check
- Ensure all emergency stop buttons on the machine are released. Then, press the RESET button on the control panel to re-engage the servos.
2Normal power-on state
- Points to it
- Alarm 102 is the normal state of the servos immediately after the machine is powered on, before they are activated.
- Check
- If no other alarms are present and you've just powered up, press RESET (and POWER UP if required by the machine) to turn the servos on.
3Another alarm removed servo power
- Points to it
- Alarm 102 can be triggered by another underlying alarm that causes the control to remove power from the servos as a safety measure.
- Check
- Open the ALARM HISTORY on the control. Look for any other alarms that appeared just before or simultaneously with Alarm 102. Address that primary alarm according to its specific troubleshooting instructions before attempting to reset.
Next check: If Alarm 102 returns immediately after pressing RESET, or if you also see Alarm 2001 EMERGENCY STOP SWITCH ERROR, it indicates that the underlying issue (possibly with the E-stop circuit itself) is still active and needs further investigation.
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