Rockwell Automation 1902 Syncpro II - Manual (Page 13)

Rockwell Automation Publication 1902-IN001B-EN-E - April 2013 13
Product Description Chapter 1
Analog/Digital Pulse Board
This board converts the voltage sinusoidal waveform across the discharge resistor
and, by examining the zero crossings, creates a digital pulse train of an equal
frequency to the induced slip frequency occurring in the discharge resistor. At
start (zero speed), the frequency will be 60 Hz, at 95% speed, the frequency will
be 3 Hz (for a 60 Hz system). This feedback is used by the SyncPro II to
determine the speed of the motor at any time during acceleration and when the
motor has reached the desired speed set point to synchronize.
Input/Output Descriptive
Control Listing
NOT STOP INPUT (I:2/0)
This signal must be maintained high for the SyncPro II to operate. When the
signal is taken low, the software identifies this as a normal stop for the motor.
The NOT STOP signal must be given in parallel to that of the hardware, i.e.
from the same PLC output or push button.
START INPUT (I:2/1)
The rising edge of this signal starts the operation of the SyncPro II. This signal is
maintained high for two-wire control or may be dropped after initial starting if
three-wire control is used. In both cases, this signal controls the START output.
After a fault has occurred, this input must be taken low before another start
command will be recognized (see
Figure 4 and Figure 5 ).
RUN OUTPUT (O:0/1)
This output is used to control motor starting. It is the START input conditioned
by all permissives. That is to say that this output will follow the state of the input
as long as all permissives are met. Thus in two-wire control, this output is actually
a RUN command and will stay high until either a fault occurs or a stop is issued.
In three-wire control the output is maintained only as long as the input is
maintained, a fault occurs, or a stop is issued.
IMPORTANT The SyncPro II does NOT have control over stopping the motor. The main
portion of the motor controller performs this control function.