Testing Methane Sensor

TESTING METHANE SENSOR

1. Toggle on/off toggle switch to the on position: This will activate the electronic shutdown system electronics. The four display LEDs on the display panel will all light up for approximately five seconds. This serves to test all the display LEDs and some of the circuitry. If there is no methane in the air, the two methane indicators will go out and only the charge failure and the run solenoid display LEDs will be on. The solenoid has not yet been activated, hence the run solenoid display LED.

2. Wait for methane sensor to read: The methane sensor needs approximately 17 seconds to warm up and measure the methane content of the surrounding air. When the waiting time is up, the solenoid will power up, the run solenoid display LED will go out and pilot air pressure will be supplied to the shut off valve. The engine is now ready to be started. Once the system has been activated and there is no methane in the surrounding atmosphere it will remain on for ten minutes. If the engine is not started in this ten minute period the system will turn itself off. To restart the system simply toggle the on/off toggle switch off and then on.

3. Start the machine: After the engine has started, the charge failure display LED will go out if the alternator is charging.

4. Place the test cap over the methane sensor and turn on the calibrated test gas:

The sensor has been calibrated to a predetermined low and high setting typically 1% for low methane and 1.25% for high methane. If a 1% calibrated test gas is passed over the methane head the low alarm display LED on the display will light up as a warning but the engine keeps running. If a 1.25% or higher calibrated test gas is passed over the methane sensor, the low and high alarm display LEDs and the run solenoid display LED on the display will light up and the engine will shutdown.

5. Remove the cap to allow fresh air to pass over the sensor: The sensor will continue checking for methane. Once no methane is registered the high and low warning display LEDs will go out, the solenoid will power up and the run solenoid display LED on the display will go out leaving only the charge failure display LED on. Pilot air pressure is then supplied to the shut off valve. The engine is now ready to be restarted.