Rockwell Automation 1901 SyncPro - Manual (Page 25)

Installation 3-7
1901-UM020C-EN-P – June 2013
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. Once
the ESR has dropped out (detected by the loss of I:4/07), 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 such as a
power factor trip.
SUMMARY
1. The RUN output will follow the state of the START input,
given that there are no faults detected by the SyncPro.
2. Once a fault has been 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 is only notified of the stoppage in
order 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.