Torque limiting function

The torque limit function is used to accurately control and limit the torque in order to prevent overload of the motor,
electricity supply system or VFD itself. This prevents damage to the motor when stationary, for example, with a
locked rotor, when starting with high inertia or high initial friction load.

The torque limit function can also be used to prevent or limit the return of power from the motor to the VFD in the event
of an over-hauling load causing the motor speed to exceed the commanded speed.

Spinning start (Flying start)

The RMVC 5100 can automatically identify that the motor is already spinning at the moment of the start request and
institute a controlled sequence to enable the drive to pick up the spinning motor without the need to stop the motor or
the risk of a system trip. The sequence requires an initial estimate of the spinning motor speed by scanning the
motor voltage while changing the output frequency. Steps are taken to reduce the time needed to estimate the motor
speed.

Examples of when a Flying Start would be used

∙ The mechanical load causes the motor to be spinning, even though no electric power is applied to the motor.
∙ Manual reset after trip
∙ Automatic restart after a shutdown.
∙ Restart after Low-Voltage Ride-Through (temporary loss of supply power).
∙ Restart after an automatic Power Cell Bypass.