A30079 — Power unit: referred to the supply voltage, the DC link voltage is too high

The power unit reports that, referred to the supply voltage, the DC link voltage is too high: the device supply voltage (p0210) was reduced, and the DC link voltage still present is too high for this new, lower supply voltage. DC link precharging cannot be completed, because this could place some converter components at risk. The drive's configuration decides whether the condition is signalled as this alarm or with no reaction (N).

• The device supply voltage (p0210) was reduced.
• At the same time, a DC link voltage is present that is too high when referred to the new supply voltage — the alarm is only output if both conditions are satisfied simultaneously.
• As a result, DC link precharging cannot be completed, since continuing could place some converter components at risk.

1. Read the alarm value in r2124, interpreting it as a decimal number: it gives the voltage to which the DC link voltage must, in the meantime, be reduced in order to complete precharging.
2. As a minimum, reduce the DC link voltage to the voltage specified in the alarm value.
3. Wait for the alarm to clear on its own — it is withdrawn automatically once the DC link voltage drops below the voltage specified in the alarm value.
4. While the alarm is active, do not try to enable the pulses: the drive then outputs fault F07802.

• The alarm value is stored in r2124 and must be interpreted as a decimal number.
• It contains the voltage value to which the DC link voltage must, in the meantime, be reduced in order to complete precharging, in volts [V].

• p0210 (Drive unit line supply voltage / U_connect) — the device supply voltage whose reduction is the trigger of this alarm; the DC link voltage is judged against the value stored here.
• r2124 (Alarm value) — read here, interpreted as a decimal number, the voltage to which the DC link voltage must be reduced so that precharging can be completed.

No acknowledgement action is required: the alarm is withdrawn automatically as soon as the DC link voltage drops below the voltage specified in the alarm value (r2124). Do not enable the pulses in the meantime — if an attempt is made to enable the pulses while the alarm is still active, the drive outputs fault F07802.