Rockwell Automation 1902 Syncpro II - Manual (Page 30)

32 Rockwell Automation Publication 1902-IN001B-EN-E - April 2013
Chapter 3 Installation
In this case (three-wire) since the START signal is only momentary, the hardware
must perform the sealing function using the control relay, CR. The START
output is really an extension of the START input, except that the output is
conditioned by any fault conditions.
The ESR circuit ensures the motor is stopped for any fault condition occurring
either externally or when detected by the SyncPro II. Once the ESR has dropped
out, a start will not be permitted until the fault condition is reset.
It should be noted that in all cases, the TRIP output is removed when a fault is
detected. This fault includes both external hardware faults (as recognized by the
EQUIPMENT SHUTDOWN signal) and faults which are generated by the
SyncPro II such as a power factor trip.
Summary
1. The RUN output will follow the state of the START input, given there are
no faults detected by the SyncPro II.
2. Once a fault is detected, the START input must be taken low before the
RUN output will be allowed to operate.
3. All motor stopping must be controlled by hardwired control circuit logic.
The SyncPro II is only notified of the stoppage to determine what is
happening. Any time the motor stops without first removing NOT STOP
input, an error condition will be detected.
4. When using three-wire control, a contact from the CR relay must be used
to seal in around the RUN output.