Teledyne 2120XL, Operating Instructions Manual, Page: 74 / 85

Operation Model 2120XL
Teledyne Analytical Instruments 62
 Latching? Ltch– Y/N (Yes/No).
To define the setpoint, use the ◄► arrow keys to move the
blinking over to
AL–1 ####
. Then use the ▲ / ▼ arrow keys to change the
number. Holding down the key speeds up the incrementing or
decrementing. (Remember, the setpoint units are ppm N
2
.)
To set the other parameters use the ◄► arrow keys to move the
blinking over to the desired parameter. Then use the ▲ / ▼ arrow keys to
change the parameter.
Once the parameters for alarm 1 have been set, press
Alarms
again,
and repeat this procedure for alarm 2 (AL2).
To reset a latched alarm, go to
Dft–
and then press either ▲ two
times or ▼ two times to toggle
Dft
from
Y
and then back to
N
.
–OR –
Go to
Ltch–
and then press either ▲ two times or ▼ two times.
(Toggle it to N and back to Y
.
)
4.6 The Analyze Function
Normally, all of the functions automatically switch back to the
Analyze
function when they have completed their assigned operations.
Pressing the ESCAPE button in many cases also switches the analyzer
back to the
Analyze
function. Alternatively, you can press the
ANALYZE button at any time to return to analyzing your sample.
4.7 Signal Output
The standard Model 2120XL Analyzer is equipped with two 0–1
VDC analog output terminals accessible on the back panel (one
concentration and one range ID), and two isolated 4–20 mA DC current
outputs (one concentration and one range ID).
See
Rear Panel
in Chapter 3,
Installation
, for illustration.
The signal output for concentration is linear over the currently
selected analysis range. For example, if the analyzer is set on range that
was defined as 0–100 ppm N
2
, then the output would be:
ppm
N
2
Voltage Signal
Output (VDC)
Current Signal
Output (mA dc)
0 0.0 4.0