F07450 — LR: Standstill monitoring has responded

The manuals title this message LR: Standstill monitoring has responded. The LR standstill monitoring expects the drive to stay inside the standstill window (p2542) for the whole of the standstill monitoring time (p2543); if the drive has left the window when that time expires, the drive raises F07450. The fault carries no message value. Depending on how the drive is configured, the same condition can also be output as an alarm (A); in that form it triggers no reaction and requires no acknowledgement.

• The position actual value inversion is set incorrectly (p0410).
• The standstill window is set too small (p2542).
• The standstill monitoring time is set too low (p2543).
• The position loop gain is too low (p2538).
• The position loop gain is too high, so the drive becomes unstable and oscillates (p2538).
• The drive is mechanically overloaded.
• The connecting cable between the motor and the drive converter is incorrect — a phase is missing or interchanged.
• Tracking mode is not selected although motor identification is selected; it must be set with BI: p2655[0] = 1 signal.
• Tracking mode is not selected although the function generator is selected (BI: p2655[0] = 1 signal), or position control is not deactivated (BI: p2550 = 0 signal).

The manual's remedy reads Check the causes and resolve. A practical order:

1. Check the setting of the position actual value inversion (p0410).
2. Check whether the standstill window (p2542) is too small and enlarge it if required.
3. Check whether the standstill monitoring time (p2543) is too low and increase it if required.
4. Check the position loop gain (p2538) in both directions: a gain that is too low and a gain that is too high (instability/oscillation) can both trigger the fault.
5. Check the mechanical system for overload.
6. Check the connecting cable between the motor and the drive converter for a missing or interchanged phase.
7. If motor identification is selected, select tracking mode (BI: p2655[0] = 1 signal).
8. If the function generator is selected, select tracking mode (BI: p2655[0] = 1 signal) and deactivate position control (BI: p2550 = 0 signal).

• p2543 (LR standstill monitoring time): check whether it is set too low.
• p2542 (LR standstill window): check whether it is set too small.
• p0410 (encoder inversion actual value): check whether the position actual value inversion is set correctly.
• p2538 (LR proportional gain): check whether the position loop gain is too low or too high (instability/oscillation).
• p2655 (BI: EPOS select tracking mode): must carry the 1 signal when motor identification is selected.
• p2550 (BI: LR enable 2): must carry the 0 signal to deactivate position control when the function generator is selected.

Once the causes have been checked and resolved, the fault can be acknowledged immediately, and the drive is then started again. The fault response stops the drive along the OFF1 response (OFF2 and OFF3 can be set as alternatives). When the condition is output as an alarm (A), no acknowledgement is required.