Teledyne BDS-3960 - Oxygen analyzer - Manual (Page 55)

Oxygen Analyzer Maintenance
Teledyne Analytical Instruments 55
as 0–1000 ppb, range 3 cannot be set as 0– 500 ppb since
it is lower than range 2.
Note: Refer to Section 4.3.2.2 to find maximum working range.
4.6.2 Fixed Range Analysis
The autoranging mode of the instrument can be overridden, forcing
the analyzer DC outputs to stay in a single predetermined range.
To switch from autoranging to fixed range analysis, click on the list
box of the main screen, as shown on figure 4.3, then select on the range
of interest.
4.8 Signal Output
The standard Model BDS 3960 Oxygen Analyzer is equipped with
two 0–1 VDC analog output terminals (one concentration and one range
ID), and two isolated 4–20 mA DC current outputs (one concentration
and one range ID) accessible from the 50-pin equipment interface
connector located on the back panel.
See Rear Panel in Chapter 3, Installation, for illustration and pin
configuration of the interface connector.
The signal output for concentration is linear over the currently
selected analysis range. For example, if the analyzer is set on a range
that was defined as 0–100 ppb O
2
, then the output would be as shown in
Table 4-2.
Table 4-2: Linear Output for a 0-100 ppm O2 Range
Voltage Signal Current Signal
ppb O
2
Output (VDC) Output (mA DC)
0 0.0 4.0
10 0.1 5.6
20 0.2 7.2
30 0.3 8.8
40 0.4 10.4
50 0.5 12.0