Teledyne 7120 - NDIR analyzer User Manual
Page 14

2 Installation
Model 7120
2-6
Teledyne Analytical Instruments
0-1 V O/P
% RANGE
VOLTAGE
0-1 V O/P
RANGE ID
4-20mA O/P
% RANGE
4-20mA O/P
RANGE ID
+
+
+
+
Press here to
insert wire.
Release to hold.
Insert wire
here.
CURRENT
Negative
ground
Floating
Current
Optional
E
x
a
m
p
l
e
s
:
The analog output signal has a voltage which depends on gas concen-
tration relative to the full scale of the range. To relate the signal output to the
actual concentration, it is necessary to know what range the instrument is
currently on, especially when the analyzer is in the autoranging mode.
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
Examples:
The analog output signal has a voltage which depends on gas concen-
tration relative to the full scale of the range. To relate the signal output to the
actual concentration, it is necessary to know what range the instrument is
currently on, especially when the analyzer is in the autoranging mode.
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 0–10 % hydrogen, then the output would be as shown in Table 2-3.
Table 2-3: Analog Concentration Output—Example
Percent
Voltage Signal
Current Signal
CO
Output (V dc)
Output (mA dc)
0
0.0
4.0
1
0.1
5.6