Sierra Monitor Corporation 2050-10 - Manual (Page 8)

Instruction Manual
Page: 2050/2060 Gas Monitors (5/04)
4.0 ALARM CALIBRATION
4.1 Factory Alarm Calibration
The module has been factory calibrated to alarm as
indicated in Table 4.1 and as marked on the cali-
bration label shipped with the module.
Model Time Gas cc/min
2050-XX 100 sec. 100 ppm NH
3
50
2060-XX 60 sec. 500 ppm R11 50
500 ppm R12 50
50 ppm R22 50
100 ppm R113 50
70 ppm R123 50
50 ppm R134a 50
40 ppm R141b 50
40 ppm R142b 50
40 ppm R500 50
70 ppm R502 50
Table 4.1
4.2 Frequency of Alarm Calibration Check
The manufacturer recommends that the calibration
of each gas sensor module be verified monthly dur-
ing the first three months of operation and then quar-
terly. More frequent checks are necessary during
periods of extreme humidity and temperature
changes. The monitor should have operated con-
tinuously (uninterrupted) for at least 24 hours prior
to calibration adjustment.
4.3 Alarm Calibration Check Process
The output signal of the gas sensor module is calibrated
using a calibration gas mixture containing a known
concentration of the gas of interest and a balance of air,
or using a substitute gas. The concentration of the span
gas must be equal to the alarm point desired.
The equivalent substitute gas is 80 ppm Hydrogen (H
2
)
for the Model 2050 and 150 ppm Carbon Monoxide
(CO) for the Model 2060.
Calibration requires application of the span gas to the
sensor and adjustment of the sensitivity adjustment po-
tentiometer.
Warning: During calibration the alarm will turn on and
remote alarms connected to the alarm relays will be
activated. Disable the remote alarm if necessary.
Fig. 4-1 Location of Calibration Voltmeter Connections and Adjustments
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