What causes Haas alarm 102?

Emergency stop button pressed or E-stop circuit opened by door interlock, rope switch, or external safety device. Servo drive fault on one or more axes causing MOCON to disable entire servo system for safety. Loss of communication between MOCON and servo amplifiers via serial encoder bus or control wiring harness. Power supply board PSUP fault or low DC bus voltage to servo amps below threshold for safe operation. Parameter corruption or setting error causing servos to disable on power-up or during initialization sequence.

How do I fix Haas alarm 102?

1. Step 1: Check all E-stop buttons are released and rotated to unlock position, verify door interlocks closed and safety circuit continuity present 2. Step 2: Press RESET button and attempt to clear alarm - observe if servos re-enable or if additional fault alarms are generated 3. Step 3: Navigate to Diagnostics > Servos page and check status of each axis servo amplifier for fault codes or communication errors 4. Step 4: Check DC bus voltage on PSUP board or in Diagnostics - verify voltage between 325-375 VDC for proper servo amp supply 5. Step 5: Inspect servo amp LED indicators on each axis drive module - solid red indicates drive fault, no LED indicates no power or communication loss 6. Step 6: If no other faults present, cycle power completely and observe boot sequence - if servos do not enable check MOCON board health and Parameters 1-50 for servo enable settings

Haas codes

axismd.ai

Haas Controller

Servo/Axis · Intermediate · 20-45 minutes

Alarm 102

Haas 102 - SERVOS OFF | Haas CNC Alarm

This alarm means the servo system has been disabled and axis drives are not energized, preventing any machine motion. The MOCON has shut down the servo amplifiers due to a fault condition, E-stop activation, or intentional servo disable command. This is a protective state that removes power from the servo amps and requires the condition to be cleared before servo enable can be restored.

HaasServo/AxisIntermediate20-45 minutes

102

Haas 102 - SERVOS OFF | Haas CNC Alarm

SERVOS OFF

Safety

Tool position may be wrong

Common Causes

Emergency stop button pressed or E-stop circuit opened by door interlock, rope switch, or external safety device
Servo drive fault on one or more axes causing MOCON to disable entire servo system for safety
Loss of communication between MOCON and servo amplifiers via serial encoder bus or control wiring harness
Power supply board PSUP fault or low DC bus voltage to servo amps below threshold for safe operation
Parameter corruption or setting error causing servos to disable on power-up or during initialization sequence

Troubleshooting Steps

1Step 1: Check all E-stop buttons are released and rotated to unlock position, verify door interlocks closed and safety circuit continuity present
2Step 2: Press RESET button and attempt to clear alarm - observe if servos re-enable or if additional fault alarms are generated
3Step 3: Navigate to Diagnostics > Servos page and check status of each axis servo amplifier for fault codes or communication errors
4Step 4: Check DC bus voltage on PSUP board or in Diagnostics - verify voltage between 325-375 VDC for proper servo amp supply
5Step 5: Inspect servo amp LED indicators on each axis drive module - solid red indicates drive fault, no LED indicates no power or communication loss
6Step 6: If no other faults present, cycle power completely and observe boot sequence - if servos do not enable check MOCON board health and Parameters 1-50 for servo enable settings

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