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7. OPERATION, TESTING
a. POWER ON: When 120VAC power (for models STCH-1000, STCH-1000LC,
STCH-1000HW, STCH-1000HWR) or 12VDC power (for model PSM-011) is
applied, the natural (methane) gas detector requires a warm-up period to stabilize
the sensor element of approximately 3 minutes. The green LED will flash during
this period. When the green LED lights on solidly, the detector begins to detect
natural (methane) gas concentrations once a second.
b. TROUBLE CONDITION: The internal micro-controller continuously monitors the
sensor and other critical components. If an internal failure of any of these
components occurs, the detector will flash the red LED and buzzes four times
every 30 seconds. Please see Section 12 for information regarding service.
c. LIFE MONITOR (END-OF-LIFE) CONDITION: The natural (methane) gas sensor
has life expectancy of 5 years. The micro-controller monitors the total time that
the detector is under power. After 5 years of service, the “End-of-Life” signal will
be activated; the detector will flash the red LED and beep once in every 30
seconds, indicating that sensor life has expired and the detector should be
replaced.
d. ALARM MODE: When natural (methane) gas concentration exceeds calibrated
level (10-25% L.E.L.), the detector will sound ”beep-beep” and turn on the red
LED. If this dangerous condition lasts for 4 seconds, the natural (methane) gas
detector will latch on alarm mode for 5 minutes with the red LED turning on and
the buzzer sounding continuously. During this 5 minutes period, the detector will
cease sensing gas concentrations and the green LED will flash to indicate the
same condition in warm-up. If the natural (methane) gas level still persists beyond
the calibrated level after 5 minutes, the detector will continue to alarm until the
natural (methane) gas clears.
e. TESTING:
IMPORTANT!
TEST MONTHLY TO ENSURE PROPER
OPERATION.Test the detector by pushing the
TEST/RESET
button on the cover
and hold it down. This will simulate a concentration of a natural (methane) gas
exceeding the safety level. If all the electronic circuit and buzzer module are
working, the detector will turn on the red LED and sound the buzzer continuously.
Do not try to test this detector in any other way.
If the detector does not respond properly, check the fuse or circuit breaker
supplying power to the detector circuit. If the detector still does not sound the unit
may be defective or have other failure and should be returned for service (see
section 12).
An erratic or low sound coming from your detector may indicate a defective
detector, and it should be returned for service (see section 12).
