User Manual

19
Testing the 4-20mA current loop
1. Connect the 200 ppm cylinder of carbon monoxide to the regulator.
2. Check the pressure gauge. If there is 25-psi or less the cylinder should be replaced.
3. Place the cap from the regulator over the CO sensor. Turn on the regulator to start the gas flow.
4. The Fan relay should activate according to the settings.
5. The Alarm relay should activate according to the settings.
6. The 4-20 mA output should ramp up from 4mA in clean air to 20mA at 200 ppm. See 4-20 mA diagram on page 6.
Note: If the 4-20mA output does not ramp up within 2 minutes, there are four possibilities:
a. Gas cylinder is empty, check the pressure gauge. Replace the gas cylinder if 25-psi or less.
b. Unit needs to be re-calibrated (go through recalibration and re-test).
c. Detector is in need of servicing (return unit to factory for servicing).
d. Detector has 4-20 mA option set to “OFF”. Set 4-20mA option to “On” and repeat the test.
7. Remove the gas from the sensor. Re-assemble the CM-12 (make sure the LED is aligned with the front case hole). You are
done.
Aerosol Carbon Monoxide Test
The CME1-FTG is an 11L 500 ppm Aerosol Carbon Monoxide Field Test Gas that can be used with the CM-12. This field test gas
allows installers to do a quick functionality test of the CO sensor. The flow rate of the CME1-FTG is 10 Lpm so you will have about a
minute of gas or enough to test 20-30 sensors.
1. Units to be tested must be powered continuously for a minimum of 3 minutes before proceeding.
2. For optimum test results the unit should be in clean air and be in a low ambient air flow.
3. Check that the CM-12 status indicator light is illuminated, Green continuously. If not, do not proceed with tests. See CM-12
Onboard Diagnostics section.
4. The display option should be set to “On” and reading 0 ppm in clean air.
5. With the CM-12 cover on, aim the nozzle of the aerosol can into the sensor grate area (under DO NOT PAINT) and press for 2
to 3 seconds.
6. Wait for a few seconds. The digital display should climb indicating the increased CO concentration at the sensor confirming a
pass of the quick test.
Note: If the Display does not change within 10 seconds, there are four possibilities:
a. Gas cylinder is empty, replace the gas cylinder.
b. Unit needs to be re-calibrated (go through the Field Calibration Procedure and re-test).
c. Detector is in need of servicing (return unit to factory for servicing).
7. Wait for the display to return to 0 ppm and configure options to desired settings.
FIELD CALIBRATION PROCEDURE
Note: For optimum calibration results the unit should be in clean air and be in a low ambient air flow.
1. Remove the Philips screw on the front of the CM-12. Pull the front cover of the unit off.
2. Assemble the 200 ppm gas cylinder and regulator together.