Rockwell Automation 1902 Syncpro II - Manual (Page 39)

Rockwell Automation Publication 1902-IN001B-EN-E - April 2013 41
Programming SyncPro II Chapter 5
Figure 15 - Running Mode
In the Running mode, the slip frequency and power factory is displayed. During
normal operation, the slip frequency is 0 Hz, and power factor is approximately
100% for unity.
View Set Points Figure 16 - Minimum Slip Frequency
Set Point 1: Minimum Percent Synchronous Slip Frequency
This set point determines the percentage of synchronous speed at which the DC
voltage is to be applied by the field switch/contactor. The SyncPro II monitors
the frequency of the induced voltage across the discharge resistor during starting.
When this frequency indicates that the motor has achieved the desired sub
synchronous speed at which it is allowable to synchronize, the SyncPro II
energizes the coil of the field switch/contactor. The SyncPro II ensures that the
application of the field contactor coincides with the rising edge of the induced
voltage waveform which makes for a smooth transition. If the motor pulls into
synchronism due to reluctance torque, the SyncPro II will detect no pulses and
then will apply DC voltage to the field after a one second delay.
operating
slip Minimum
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1
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