F07403 — Drive: Lower DC link voltage threshold reached

F07403 (Drive: Lower DC link voltage threshold reached) means that the DC link voltage monitoring was active and the DC link voltage fell to its lower threshold while the drive was in the Operation state. The manual describes this code for the G130, G150, S120 and S150. Depending on the drive's configuration, the same condition can also be signalled only as an alarm (A) or without any reaction (N). Issued as a fault, the drive executes OFF1 and the message must be acknowledged immediately before the drive can run again.

The cause is the same in substance for all drive objects; what differs between VECTOR and SERVO drive objects is which parameters configure the monitoring and which threshold is monitored:

• VECTOR drive objects (G130/G150 and S120/S150): the DC link voltage monitoring is active (p1240, p1280 = 5, 6) and the lower DC link voltage threshold (r1246, r1286) was reached in the Operation state.
• SERVO drive objects: the DC link voltage monitoring is active (p1240 = 5, 6) and the lower DC link voltage threshold (p1248) was reached in the Operation state.

1. Check the line supply voltage.
2. Check the infeed.
3. Adapt the device supply voltage (p0210) or the switch-on level (p1245, p1285). On SERVO drive objects, reduce the lower DC link voltage threshold (p1248) instead.
4. Disable the DC link voltage monitoring (p1240 = 0, and p1280 = 0 where this parameter is used).

• p1240 — Vdc controller or Vdc monitoring configuration: the monitoring is active when it is set to 5 or 6, and setting it to 0 switches the monitoring out.
• p1280 — Vdc controller or Vdc monitoring configuration (U/f): the second configuration parameter named in the cause; active at 5 or 6, disabled at 0.
• r1246 — Vdc_min controller switch-in level (kinetic buffering): the lower DC link voltage threshold whose reaching raises the fault on VECTOR drive objects.
• r1286 — Vdc_min controller switch-in level (kinetic buffering) (U/f): the corresponding lower threshold for the U/f configuration.
• p0210 — Drive unit line supply voltage: adapt this setting so it matches the actual line supply voltage.
• p1245 — Vdc_min controller switch-in level (kinetic buffering): the switch-on level you adapt so that the lower threshold is no longer reached during operation.
• p1285 — Vdc_min controller switch-in level (kinetic buffering) (U/f): the corresponding switch-on level for the U/f configuration.
• p1248 — DC link voltage threshold lower: the lower DC link voltage threshold on SERVO drive objects; the remedy is to reduce it.

The fault is acknowledged immediately. Once the cause has been corrected and the fault acknowledged, the drive can be restarted. Where the drive's configuration signals the same condition only as an alarm (A) or without any reaction (N), neither a reaction nor an acknowledgement applies.