Macurco OX-12 Instructions D'utilisation page 21

3. Check the pressure gauge on the regulator. If you have 25-psi or less you will need to replace the gas canister.
4. Assemble regulator, hose and test hood and place the test hood over the gas sensor.
Note: The time to activate the Fan relay depends on the delay setting.
5. Turn on the regulator to start the gas flow and wait with the gas applied continuously.
6. With the display function turned "On", the OX-12 will show the current concentration of gas or "20.9" (% v/v) in clean air. When
the gas concentration reaches the Fan Relay setting (20.2% v/v, for example) the display will flash back and forth between
"FAn" and "20.2". With the display function turned "OFF", the display does not show the gas concentration, but will show "FAn"
as long as the fan relay is activated.
Note: If the Fan relay does not close within 2 minutes, there are five possibilities:
a. Gas cylinder is empty, check the pressure gauge. Replace the gas cylinder if 25psi or less.
b. Unit needs to be re-calibrated (go through recalibration and re-test).
c. Detector has fan relay set to disable (OFF). Set fan relay to 20.2% v/v and repeat the test.
d. Detector has fan relay delay set to 3 minutes or higher. Set fan relay to 0 minutes and repeat the test.
e. Detector is in need of servicing (return unit to factory for servicing).
7. Remove the gas from the sensor. Proceed to Test the Alarm relay or replace the top cover. Fan relay test is complete.
Testing the Alarm Relay
Note: The gas concentration to activate the Alarm relay depends on the setting.
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