Calibration Check Mode; Calibration Mode - General Monitors 2180A Instruction Manual

3. Allow the sensor to see the gas for 1 to 2 minutes.
NOTE: Do not store the cylinder with the regulator fully engaged in the cylinder valve.

3.6 Calibration Check Mode

This procedure is used to periodically check the response of an installed system to a
known concentration of H
To perform a calibration check use the following procedure:
NOTE: The Calibration Check mode cannot be entered if the channel is in alarm.
1. Enter the Calibration Check mode by pressing and holding the Mode button until the
CAL LED begins to flash (about ten seconds). The channel displays the calibration
level. When the CAL LED begins to flash, release the Mode button. The channel is
now in Calibration Check mode.
2. When the Mode button is released, the display indicates a flashing pair of bars (- -)
for about ten seconds.
3. When the display indicates flashing digits, for example "0", apply the test gas to the
sensor. The display begins to go up in scale as the sensor sees gas. If no gas is
applied, the channel returns to the normal operating mode after 6 minutes.
4. The reading stabilizes after 1 to 2 minutes of exposure to the test gas. This response
time may increase due to the presence of the Dust Guard, Splash Guard or other
sensor accessories.
5. If the sensor does see the gas, the read-out on the display flashes for as long as the
unit remains in Calibration Check mode. The operator should compare the reading
with the gas concentration applied and determine if it is necessary to calibrate the
sensor.
6. Remove the gas and expose the sensor to clean air. If the gas is not removed within
6 minutes, the channel reverts to a fault condition.
7. Press the Mode button. The calibration level is displayed for a short time, and the
channel exits out of calibration check mode.
NOTE: Low and High alarms are disabled during Calibration Check mode.

3.7 Calibration Mode

This procedure is used for initial installation of the system. It is also used to re-calibrate
the system if the controller or sensor is replaced, or if the calibration check is not within
expected limits.
NOTE: For better results power up the sensor at least an hour before calibration. Make
sure the calibration gas is the same concentration as the user specified
calibration level. Recalibration is recommended after the first 24 hours.
S gas that is at least 50% of the full-scale reading.
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Model 2180A