Campbell Scientific TGA100 Trace Gas Analyzer Manual - Manual (Page 91)

To read data from a CR9000, complete the following steps:
1) Connect a cable (CSI P/N 10847) from the RS422 Link connector on the TGA 9030 CPU card to the TLink
connector on the CR9000 9031 CPU card.
2) Start the TGA program and from the Main Menu, select the Parameter Change Menu and then the File Format
screen.
3) Set the Output conc data to additional device? parameter to 0.
4) Set the Read data from additional device? parameter to 2.
Every 0.1 sec the TGA100 will request and receive 15 data fields from the CR9000. The CR9000 must be programmed
to scan its devices and then wait for the TGA100 to request data. It then sends 15 data fields to the TGA100 (null
values will be sent if fewer than 15 data fields are used), completes another measurement scan, and then waits for the
next request from the TGA100. In this way all of the measurements are synchronized to the TGA100 clock.
Any of the fifteen data values can be displayed on the real time screen in graph 1, 2, or 3, by choosing it from the graph
selection menus. These data will be written to the 10 Hz data file if selected for file output on the File Output Selection
screen.
7.3 Sending Concentration Data to a CR9000
This option is used when it is necessary to collect a large number of parameters (more than 15) in addition to the
TGA100 concentration measurement. To send concentration data to a CR9000, complete the following steps:
1) Connect a cable (CSI P/N 10847) from the RS422 Link connector on the TGA 9030 CPU card to the TLink
connector on the CR9000 9031 CPU card.
2) Start the TGA program and from the Main Menu, select the Parameter Change Menu and then the File Format
screen.
3) Set the Read data from additional device? parameter to 0.
4) Set the Output conc data to additional device? parameter to 1.
Every 0.1 sec the TGA100 will send its concentration data to the CR9000. The CR9000 must be programmed to wait
for the TGA100 to send its data, and then complete its scan of the other devices to be measured. In this way all of the
measurements are synchronized to the TGA100 clock.
7.4 TGA Analog Inputs
The TGA100 has four analog input channels on the 9058 Trace Gas Input module mounted in the electronics chassis
inside the analyzer enclosure. Channels one through three are available for use as auxiliary inputs, and record the raw
input voltage only. They are always measured, regardless of parameter settings. The measurement results can be viewed
on the real time screen by selecting TGA Analog 1, TGA Analog 2, or TGA Analog 3 for display in graph 1, 2, or 3.
These data will be written to the 10 Hz data file if selected for file output on the File Output Selection screen.
Table 12. TGA (9058) Analog Input Channels
Wire
Locations
9058
Channel
Range
(volts) Resolution
(bits)
Sampling
Frequency (Hz)
Notes
1 & 2 1 ± 5 16 10
3 & 4 2 ± 5 16 10
5 & 6 3 ± 5 16 10
7 & 8 4 ± 5 16 10 Used for analyzer pressure measurement
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