Cause : Precharging monitoring time expired comes when the line contactor closes the power unit does not signal the READY state within the monitoring time (p0857).

The end of the DC link pre-charging was not able to be completed for one of the following reasons:
1) There is no line supply voltage connected.
2) The line contactor/line side switch has not been closed.
3) The line supply voltage is too low.
4) Line supply voltage incorrectly set (p0210).
5) The pre-charging resistors are overheated as there were too many pre-charging operations per time unit.
6) The pre-charging resistors are overheated as the DC link capacitance is too high.
7) The pre-charging resistors are overheated because when there is no "ready for operation" (r0863.0) of the infeed unit, power is taken from the DC link.
8) The pre-charging resistors are overheated as the line contactor was closed during the DC link fast discharge through the Braking Module.
9) The DC link has either a ground fault or a short-circuit.
10) The pre-charging circuit is possibly defective (only for chassis units).

See also: p0210 (Drive unit line supply voltage), p0857 (Power unit monitoring time)

- check the line supply voltage at the connecting terminals.
- check the line supply voltage setting (p0210).
- check the monitoring time and, if required, increase (p0857).
- where relevant, observe additional power unit messages/signals (e.g. F30027).
- the following applies to booksize units: Wait (approx. 8 min.) until the pre-charging resistors have cooled down. For
this purpose, preferably disconnect the infeed unit from the line supply.

Re 5): - carefully observe the permissible pre-charging frequency (refer to the appropriate Equipment Manual).

Re 6): - check the total capacitance of the DC link and reduce in accordance with the maximum permissible DC-link
capacitance if necessary (refer to the appropriate Equipment Manual)

Re 7): - interconnect the ready-for-operation signal from the infeed unit (r0863.0) in the enable logic of the drives connected
to this DC link

Re 8): - check the connections of the external line contactor. The line contactor must be open during DC-link fast discharge.

Re 9): - check the DC link for ground faults or short circuits.