CO230-en-GB_v1.0 1/16
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NOTES:
1. If the meter has been powered on for less than 15 minutes, the
STEL value will be the weighted average of readings taken since
power on. The TWA mode will display a weighted average of the
readings taken during the prior 8 hours of operation.
2. The CO230 requires at least 5 minutes to calculate STEL and
TWA values. The display shows “----” during this time.
ALARM OVERVIEW
Audio-visual alarms give warnings when CO
2
concentration exceeds
the high limit. The meter beeps (~80dB) and flashes the LED when
the CO
2
level exceeds the high limit. The beeper stops when any key
is pressed or if the reading falls below the low setpoint limit.
Press and hold SET to stop the beeper. The LED lamp will continue to
flash when the beeper is manually shut off if there is still an alarm
condition. The LED will stop flashing when readings return to normal.
ALARM RELAY OUTPUT
The meter includes an internal reed relay that can be connected to
an external device (not supplied). When the CO
2
readings exceed the
high limit, the relay closes. When the CO
2
readings fall below the low
limit, the relay will open. This relay can be used to switch in an
external device. The meter can be connected to a device to control
such things as alert signs/beepers or ventilation systems for
conditioning the air quality.
