Teledyne 2000XTC - Thermal conductivity analyzer - Manual (Page 31)

Thermal Conductivity Transmitter Installation
To span calibrate this instrument:
1. Connect a read-out device to the 4-20 mA output signal
terminals on the galvanic isolator module according to
Section 3-5.
2. If the transmitter cover has not been removed, unscrew the 4
cover screws and remove the top cover.
3. Allow span gas to flow through the transmitter. After a few
moments, the output device should respond to the known
concentration of gas in the span gas mixture.
4. If the read-out device indicates a value different than the
known concentration, adjust the span potentiometer (R38) as
shown in Figure 3-5 until the readout is correct. If using a
mA current read-out device, refer to Table 3-1 to determine
concentration from the output current.
5. If the zero calibration must be changed after initial span
calibration, recalibrate the span.
Table 3-2: Concentration from Output Current
Concentration
Current
Output
(mA)
0-1%
Full
Scale
0-10%
Full
Scale
0-50%
Full
Scale
90-100%
Full
Scale
0-100%
Full
Scale
4 0 0 0 90 0
5.6 0.1 1 5 91 10
7.2 0.2 2 10 92 20
8.8 0.3 3 15 93 30
10.4 0.4 4 20 94 40
12.0 0.5 5 25 95 50
13.6 0.6 6 30 96 60
15.2 0.7 7 35 97 70
16.8 0.8 8 40 98 80
18.4 0.9 9 45 99 90
20 1.0 10 50 100 100
Teledyne Analytical Instruments 21