Teledyne GC-Pro/TCD - Gas Chromatograph - Manual (Page 39)

GC-Pro TCD Installation
Teledyne Analytical Instruments 25
1. Test the CRC. When the CRC is open, send a span command
until the CRC closes (The CRC will quickly close.)
2. When the CRC closes, remove the span command.
When CRC opens again, the span calibration is done, and the sample
is being analyzed.
3.3.2.7 ‘M EASURE O NCE ’ ( OR ONE SHOT MEASUREMENT ) CONTACTS
There are three dedicated relay contacts and these are available from
the bottom Equipment Interface Connector. They are assigned to
indicate status of ‘measure once’ (or one shot measurement). Contacts
are normally open, and they close when GC-Pro TCD switches to that
particular range.
Table 3-5: ‘Measure Once’ Relay Connections
Pin Function
9 + Start Measurement Digital Input
11 - Start Measurement Digital Input
21 IDLE Contact 1
38 IDLE Contact 2
22 IN MEASUREMENT Contact 1
39 IN MEASUREMENT Contact 2
19 MEASUREMENT DONE Contact 1
18 MEASUREMENT DONE Contact 2
The MEASUREMENT DONE contact only closes for 5 seconds at
end of the measurement cycle. After that, the IDLE contact closes. The
display reading and analog output will then remain fixed until a new
measurement is requested.
Digital input range is 5 to 24 vdc to start measurement.
3.3.2.9 P IN O UT T ABLE
The following table summarizes all the outputs/inputs available on
the three 50 pin D-Sub connectors on the back panel of the analyzer.