Testing The 4-20Ma Loop; Aerosol Carbon Monoxide Test - Macurco CM-6 Instrucciones Para El Usuario

Macurco CM-xx Operation Manual
5. With the display function turned "On" and the CO concentration reaching the Alarm Relay setting, (200 ppm, for
example) the display will flash back and forth between "ALr" and "current gas reading". The buzzer will sound
indicating "Alarm" if the buzzer is turned "On". With the display function turned off the display does not show the CO
concentration but will show "ALr" when the Alarm relay is activated.
Note: If the Alarm relay fails to operate 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 Alarm relay set to disable (diS). Set Alarm relay to 100 ppm and repeat the test.
6. Remove the gas from the sensor after Test. Proceed to Test the 4-20mA output or replace the top cover.

7.3.3 Testing the 4-20mA 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-6 (make sure the LED is aligned with the front case hole). You
are done.

7.3.4 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-xx. 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-6 status indicator light is illuminated, Green continuously. If not, do not proceed with tests. See
CM-6 Onboard Diagnostics section.
4. The display option should be set to "On" and reading 0 ppm in clean air.
5. With the CM-6 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.
REV – 1.2 [34-2900-0511-6]
29
| P a g e