Chapter 6 – Parameters
ACH 500 Programming Manual
6-27
9 NOMINAL SLIP
For the precise operation of the Slip Compensation function, the ACH 500
must know the nominal slip of the motor. Set the nominal slip as a percentage
of the nominal motor speed with a range of 0.1 – 10.0%, 0.1% step.
10 VOLTAGE LIMIT
This parameter allows you to deactivate the Over and Undervoltage
Controllers.
The overvoltage controller will increase the output frequency if the DC bus
voltage exceeds the high DC bus voltage limit level, typically from an
overhauling load, to prevent an overvoltage trip.
The undervoltage controller will decrease the output frequency if the DC bus
voltage drops below the low DC bus voltage limit, caused by a loss of input
power. By decreasing the output frequency, the inertia of the load will cause
regeneration back into the drive, keeping the DC bus charged, and preventing
an undervoltage trip. This will increase power loss ride through on systems
with a high inertia, such as a centrifuge or fan.
Slip = (1 -
synchronous speed
nameplate speed
) x 100
