3 — APPLICATION-SPECIFIC FEATURES
pg. 27
Return to TOC Curtis AC F4-A Motor Controller – August 2020
Beyond the default or a redened normal operating window, the controller’s actions for over- and
under-voltage conditions are both voltage and time-duration based. As illustrated in the graph
and following paragraphs, these responses are xed. No parameters can change or modify the
hardware restrictions.
Over-Voltage Region
No reduction in regen, nor is the Overvoltage Cutback set within the rst 100ms. Aer this period,
the controller will seek to reduce the voltage by progressively reducing regen (motor-braking torque).
e Overvoltage Cutback fault (ash code 2-4) is set.
Severe Over-Voltage Region
Should the B+ voltage rise to this region, it triggers the Severe B+ Overvoltage fault (ash code 1-8).
Normal controller operation will cease.
Under-Voltage Region
No reduction in drive current (motor torque), nor is the Undervoltage Cutback set within the rst
100ms. Aer this period, progressive reduction in drive current occurs. e Undervoltage Cutback
fault (ash code 2-3) is set.