Models 947, 948 and 960 Leak Detectors Operations and Service Manual
3-18
Several parameters relating to the operation and performance of the 947/948/960 Platform
are stored in EPROM. These parameters are viewed and changed via the service or rear
serial ports. Some parameters are set when the system is assembled and tested. Other
parameters should be changed when a gauge is changed or when the ion source or
preamplifier is changed. Some parameters are changed automatically during power up,
Auto Cal, or Auto Zero functions. See Section G, “Leak Detection Theory” on page G-1 for
details.
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 Section D, “Inputs and Outputs” on page D-1 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
.
Summary of Contents for 948
Page 175: ......
