Over-voltage of DC Link (ECM)

What does 6 mean?

An over-voltage condition has occurred in the DC link connected to the Energy Charge Module (ECM) and Servo amplifier. This is typically caused by excessive regenerative energy from the motor that cannot be dissipated or stored, or an unstable main power supply exceeding nominal limits.

• The DC link voltage exceeds its maximum allowed limit.
• Over-voltage condition on the main DC bus.
• Regeneration occurring without adequate load or dissipation.
• Faulty voltage sensing circuit for the DC link (P-V-DC).

Click steps to track your progress.

1. 1

   Immediately stop the machine using the emergency stop button and open the external Main Circuit Contactor (MCC) of the Power supply.

2. 2

   Measure the DC link voltage at the amplifier's terminals (e.g., +UDC/-UDC) and compare it to specified thresholds (e.g., 300VDC for 200V input, 600VDC for 400V input, page 28). Confirm it exceeds the limit.

3. 3

   Verify the proper operation and capacity of the regenerative discharge unit; ensure it is effectively dissipating regenerated energy.

4. 4

   Check the main power supply voltage for any transient overvoltages or instability that could contribute to DC link over-voltage.

5. 5

   Review the motor deceleration parameters in the CNC to ensure they are not set too aggressively, causing high regenerative energy spikes.