Low-voltage of Control Power Supply (ECM)
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What does 5 mean?
The 24V control power supply voltage to the Energy Charge Module (ECM) or Servo amplifier is low. This critical condition prevents proper operation of the ECM and associated components, indicating a problem with the external 24V power source or its connections.
Repair Steps
- 1
Immediately stop the machine using the emergency stop button and open the external Main Circuit Contactor (MCC) of the Power supply.
- 2
Measure the 24V DC input voltage at the control power supply terminals to the ECM and servo amplifier; ensure it is stable and within the acceptable range (e.g., 24V ±10%).
- 3
Check the external power supply unit providing the 24V control power for proper output voltage and sufficient capacity.
- 4
Inspect the wiring and connections of the 24V control power supply for any loose connections, breaks, or excessive voltage drop due to long or undersized cables.
- 5
Verify the total load on the 24V control power supply. Excessive load from other devices could cause the voltage to drop below acceptable levels.