A07899 — Drive: Stall monitoring not possible

A07899 tells you that stall monitoring is not possible in the current parameterization: the drive changed over into the open-loop speed controlled mode before the stall detection wait time p2177 had expired. The message can only occur in the encoderless open-loop speed controlled operating mode and is remedied through parameters, not through hardware measures. Depending on how the message is configured, the drive can also output this condition with no reaction (N).

• Stall monitoring is not possible because a changeover into the open-loop speed controlled mode was made before the wait time p2177 had expired.
• This situation can only occur when all of the following conditions apply at the same time:
• p1300 = 20, i.e. the drive is in the open-loop speed controlled operating mode.
• p2177 > p1758.
• p1750.2 = 0.
• p1750.6 = 0.

1. Deactivate the changeover into open-loop speed controlled operation when operating at the torque limit (p1750.6 = 0). This is only permissible if the drive does not reverse slowly through the open-loop speed controlled operating range p1755 within the time p1758 while operating at the torque limit.
2. Shorten the stall detection wait time so that p2177 < p1758.
3. Activate closed-loop controlled operation from standstill and higher (p1750.2 = 1). This is only permissible if there is no active load, for example a hoisting gear.
4. Use an operating mode with encoder (p1300 = 21).

• The drive enters the number of the parameter concerned into the message value (shown as "Parameter: %1").
• No bit-by-bit decoding of the message value is given for this message.

• p1300 (Open-loop/closed-loop control operating mode): the message can only occur with p1300 = 20; one remedy is to select an operating mode with encoder by setting p1300 = 21.
• p2177 (Motor blocked delay time): the stall detection wait time; the message appears if the changeover happens before it expires, and one remedy is to shorten it so that p2177 < p1758.
• p1758 (Motor model changeover delay time closed/open-loop control): the changeover delay time against which p2177 is compared.
• p1750 (Motor model configuration): the bits p1750.2 and p1750.6 are part of the trigger conditions; the remedies set p1750.6 = 0 to deactivate the changeover when operating at the torque limit and p1750.2 = 1 for closed-loop controlled operation from standstill and higher.
• p1755 (Motor model changeover speed encoderless operation): the speed of the open-loop speed controlled operating range referred to in the condition of the first remedy.

This message requires no acknowledgment. Once one of the parameter changes described above has been made so that the trigger conditions no longer apply, the situation that raised the message is removed. No further reset or acknowledgment action is specified for this message.