
04 Series for CO(-H2)
Chapter 3: Measuring Mode • 21
Alarms
This section covers alarm indications in Measuring Mode. It also describes how to reset the
CO-04C after an alarm occurs and how to respond to an alarm condition.
NOTE:
False alarms may be caused by radio frequency (RF) or electromagnetic (EMI)
interference. Keep the CO-04C away from RF and EMI sources such as radio
transmitters or large motors.
Alarm Indications
The CO-04C buzzer sounds an alarm, the LED flashes, and the vibrator pulses when any sort
of alarm condition or failure occurs. If the CO-04C is operating in Stealth Mode, the buzzer
does not sound and the vibrator’s operation depends on the
VIB
setting in Gas Select Mode’s
STEALTH
item. See pg.91 for more information.
NOTE:
If an alarm condition occurs while you are in Display Mode, the CO-04C
automatically returns to the Measuring Mode screen.
The table below summarizes the types of alarms produced by the CO-04C and their
indications.
Table 4: Alarm Types and Indications
Alarm Type
Visual Indications
Other Indications
Warning
Concentration of gas rises above the
Warning setting.
• Gas reading flashes
•
WARNING
appears at the bottom of
the LCD
• Alarm LED flashes once per second
• Backlight turns on
• High-low tone sounds
once per second
• Vibrator pulses once per
second
Alarm
Concentration of gas rises above the
Alarm setting.
• Gas reading flashes
•
ALARM
appears at the bottom of the
LCD
• Alarm LED flashes twice per second
• Backlight turns on
• High-low tone sounds
twice per second
• Vibrator pulses twice per
second
Alarm H
Concentration of gas rises above the
Alarm H setting.
• Gas reading flashes
•
ALARM H
appears at the bottom of
the LCD
• Alarm LED flashes twice per second
• Backlight turns on
• High-low tone sounds
twice per second
• Vibrator pulses twice per
second
TWA or STEL
Concentration rises above the TWA
or STEL alarm setting.
• Gas reading flashes
•
TWA
or
STEL
appears at the bottom
of the LCD
• Alarm LED flashes once per second
• Backlight turns on
• High-low tone sounds
once per second
• Vibrator pulses once per
second