The alarms are detailed below:
Instantaneous power failure compensation/under-voltage
compensation
The circuitry is protected when the supply voltage is
instantaneously cut off or when the voltage drops to an
abnormally low level.
Instantaneous overcurrent detection (OCP)
The transistors are protected when an overcurrent
momentarily flows to the transistors in the circuitry.
Overcurrent detection (OVC)
This protection circuit functions when an overcurrent has
flowed to main circuitry for more than a fixed period of
time.
Overspeed (TGOV)
The motor is protected when the motor speed exceeds its
rating due to a malfunction.
No-signal detection (NSG)
This alarm functions when the signals are no longer fed back
from the resolver to the transistor amplifier.
(This is for
detecting the magnetic pole position.)
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