18
Operation
Gas alarm operation
When the gas concentration exceeds the gas alarm set value, the unit will start
beeping, alarm light will start blinking red, “AL” or “ALARM” will appear on the LCD,
and the backlight will turn on. When the gas concentration falls below the gas alarm
set value, the gas alarm will automatically deactivate (auto-resetting).
When a high concentration gas is detected and the service range is exceeded,
“OVER RANGE” will be displayed instead of the gas concentration value. In this
case, move the detector to clean air area immediately and run it. Check that the gas
concentration value falls enough and residue gas is removed from the unit, and then
turn it off. Exposure to high concentration gas may impair the sensor performance.
Example: Typical alarm setting for a methane and oxygen detector
Gas alarm
Over range alarm
Ga
s
ty
pe
Co
mbustible
gas
20%LEL
110.1%LEL
Oxygen
18.0vol%
50.1vol%
Alarm sound
Beeping
Beeping
Alarm light
Blinks red at 0.25 sec intervals
Blinks red at 0.25 sec intervals
L
CD
Standard
display
“AL” displayed
“ALARM” displayed for 1-gas
model
“OVER RANGE” displayed
Trend
graph
display
“AL” displayed
“OVER RANGE” displayed
Press the▼ button for two seconds to silence the beeping during an
active alarm. However, if a new alarm arises, the unit will start
beeping.
The unit does not beep when the audio level is set to MUTE ( icon
is present).
NOTE