GEH-6385 Reference and Troubleshooting, 2300 V Drives Chapter 3 Paramters/Functions
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Function description
The variables Output volts, A-B and Output volts, B-C ar e filtered versions of the
measured line-line voltage feedbacks. The default filter frequency is 1000 rad/sec.
When the drive is stopped, it performs an automatic voltage offset calculation. If the
drive does not have a contactor, the offset calculation happens continuously. If a
contactor is present, the calculation occurs when th e contactor closes immediately
before the drive begins running. During the calculation the power bridge is turned off
and the line-line volta ges should be zero. Any apprecia ble voltage that is detected
during the calculation indicates a potential power bridge or feedback circuitry
problem. The A-B voltage offset and B-C voltage offset trip faults are reported when
excessive offsets ar e calculated. The calculated offs ets A-B, Voltage offset an d B-C,
Voltage offset are used by the control to calculate feedbacks once t he drive starts
running.
There is a period of time when th e line-line voltage offset calculations are considered
valid and the calculation does not need to be performed if the drive is stopped and
started again. However , if the time expires, the voltag e offsets must be recalculated
before the drive can run a gain. The default value for the ex piration time is one hour.
The variable Voltage offset valid indicates whether or not the voltage offset
calculations are va lid.
Motor Overtemperature Det ection
Innovation Series drive products pr ovide the capability to detect a motor
overtemperatur e condition. The Motor over temp trip fault and the Motor temp hot
alarm trigger on a signal that is a drive input from the motor overtemperature fault
circuit. When the motor ov ertemperature circuit is op en, the fault or alarm occurs.
Function inputs
The following table specifies the input parameters of the Motor Overtemperature
Detection function.
Parameter Description
Motor OT faul t sel Selects t he source of the mo tor overtemper ature
circuit.
Function configuration
The following table specifies the configuration parameters of the Motor
Overtemperature Detection function.
Parameter Description
Motor OT faul t mode Specif ies whether the ov ertemperatur e condition
triggers a fault or an alarm.