ALARM 51 — OVERLOAD 2
Interactive troubleshooter
Step 1 of 6Turn the main power OFF and verify that the PN voltage is correctly supplied to the drive unit. If the CHARGE lamp is dark or the L+ / L- terminal screws are loose, securely tighten the screws or increase the facility power supply capacity.
↺ Restart from step 1All diagnostic steps
Turn the main power OFF and verify that the PN voltage is correctly supplied to the drive unit. If the CHARGE lamp is dark or the L+ / L- terminal screws are loose, securely tighten the screws or increase the facility power supply capacity.
Inspect the motor power cable (U, V, W phases) and the encoder cable connections. If the cables are disconnected, improperly wired, or mistakenly connected to another axis, connect them correctly to the appropriate axis.
Check whether the machine has collided during operation or if the load meter value is abnormally high. If a collision occurred, review the machining program and soft limit settings. If the cutting load is excessively high, reduce the cutting load.
Monitor the current value on the NC Servo Monitor screen during machine operation. If the current is saturated during acceleration or deceleration, increase the acceleration/deceleration time constant.
Verify the encoder feedback. For servo axes, if the droop does not stabilize or the feedback signal is abnormal, replace the encoder (establish the zero point if using an absolute position system). For spindle axes, check the PLG output waveform and adjust it if it is abnormal.
If the power supply, cables, load parameters, and encoder feedback are normal but the Overload 2 alarm persists, the drive unit is faulty. Replace the MDS-E drive unit.