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Common Causes

• Emergency stop button is pressed or E-stop circuit is open due to faulty door interlock switch or external E-stop device
• Servo amplifier has detected an overcurrent, overvoltage, or thermal fault and has disabled itself to protect drive circuitry
• Loss of 24VDC control power to servo amps or MOCON board due to PSUP failure or blown fuse in control cabinet
• MOCON board is not sending enable signal to servo amps due to board failure or corrupted control software requiring reboot
• Faulty wiring or loose connections in the servo enable circuit between MOCON and servo amplifier enable inputs

Troubleshooting Steps

1. 1Step 1: Verify E-stop button is not pressed and all safety interlocks are closed - check door switches and external E-stop devices in the circuit
2. 2Step 2: Check Diagnostics page under MOCON inputs to verify E-stop circuit shows closed and all safety inputs are in normal state
3. 3Step 3: Power cycle the machine - turn control off, wait 30 seconds, power back on and check if servos enable after boot sequence completes
4. 4Step 4: Check for individual servo amp fault LEDs on each axis amplifier - red LED indicates amp fault, consult specific servo alarm code if present
5. 5Step 5: Verify 24VDC is present at PSUP board and measure voltage at servo amp enable inputs - should see 24VDC when control attempts to enable servos
6. 6Step 6: If all power and signals are correct but servos will not enable, check MOCON output signal to servo enable circuit using Diagnostics page outputs, then suspect MOCON board failure if no enable output is present