GasWatch 3 for CO and O
2
Chapter 2: Description • 11
Filters
Charcoal Filter (Black)
A black charcoal filter is placed into a recess in the filter gasket over the sensor. The charcoal
filter disk scrubs H
2
S and certain hydrocarbons out of the sample to avoid false CO readings.
If false or elevated CO readings are noticed, especially in the presence of H
2
S, change the
charcoal filter.
Hydrophobic Filter
The white, circular hydrophobic filter sits on the filter gasket, covering the sensor port and the
charcoal filter.
Infrared Communications Port
An infrared (IR) communications port is located at the top of the instrument, near the LEDs.
Logged data transmits through the port in standard IrDA protocol. A computer’s infrared port
or an IrDA/USB cable connected to a USB port can be used to download data to the GasWatch
3 Datalogging Program. See the GasWatch 3 Datalogging Program operator’s manual for data
logging and downloading instructions.
Battery
A user-replaceable CR2450 button cell battery powers the GasWatch 3. At 25°C the battery
lasts at least 2,000 hours (83 days). The battery icon in the upper right of the LCD shows
remaining battery life.
A low battery warning activates when the GasWatch 3 detects a low battery voltage. The
GasWatch 3 sounds a dead battery alarm when battery voltage is too low for Measuring Mode.
NOTE:
Use of batteries not specified by RKI Instruments, Inc. compromises the CSA
classification and may void the warranty. See “Replacing the Battery” on page 74.
WARNING:
To prevent ignition of a hazardous atmosphere, the battery must only be
changed in an area known to be nonhazardous.
AVERTISSEMENT:Pour éviter l'inflammation d'une atmosphère dangereuse, la batterie
ne doit être remplacée que dans une zone non dangereuse.
