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© 2020 All rights reserved. Data subject to change without notice.
cGas Detector Analog Transmitter - Operation Manual
Rev. B | 2020.07
Ascending alarm is used when monitoring a gas that becomes hazardous in
increasing quantity. The normal/safe gas level is below the alarm setpoint and
when the gas level increases, reaching and exceeding the alarm setpoint, the
alarm is tripped.
Almost all installations will use the factory default alarm setpoints. Default
setpoints are as follows:
GAS TYPE
STANDARD
RANGE
LOW
ALARM
MID
ALARM
HIGH
ALARM
Carbon Dioxide (CO
2
) 0 - 5,000 ppm 1,000 ppm 1,250 ppm 1,500 ppm
Carbon Dioxide (CO
2
) 0 - 5.0% vol
1% vol
2% vol
3% vol
Setting a hysteresis value determines at what gas concentration the alarm
condition will stop when the gas reading goes below the alarm setpoint. For
example, if the alarm setpoint is 100 ppm and the hysteresis is 5 ppm, when the
gas concentration reaches or exceeds 100 ppm, the cGas Detector will indicate
an alarm condition. It will remain in alarm condition until the gas concentration
reduces to 95 ppm (5 ppm below the alarm setpoint).
Using hysteresis prevents the alarm condition from coming on and going off
repetitively if the gas fluctuates just above and just below 100 ppm (which
would happen if the hysteresis is set to 0). Sending in alarm and out of alarm
signals to the control panel could trigger relays to repetitive turn on and off,
causing them to burn out and equipment to suffer unnecessary wear and tear.
From the main display, press ENTER.
Enter passcode 2012 using the UP button and ENTER button.
Enter Password
2012
Press ENTER to access the Alarms Menu.