Models 947, 948 and 960 Leak Detectors Operations and Service Manual
3-18
3.9 Optional Discrete I/O
To use the optional discrete I/O connections, connect to J120 and J121 on the rear panel.
Refer to Appendix D, “Inputs and Outputs” for detailed information.
When operating the 947/948/960 from the optional discrete I/O, it is necessary to make the
PARALLEL ENABLE (J120 pin 6) active. This allows the leak detector to accept commands
from the other discrete I/O inputs. Making PARALLEL ENABLE active also disallows any
changes to the operating parameters through the serial port, the service pendant, or the front
panel. Requests for changes made through the serial port would be responded to by
cant
.
