RKI Instruments M2 Series User Manual
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7
M2 Transmitter Operator’s Manual
Figure 3: 65-2494RK Oxygen Detector, Non-Explosion Proof, Capillary Type
CO and H
2
S Detectors
Both types of CO and H
2
S detectors have replaceable plug-in sensors inside the detector
housing. The CO detector includes a charcoal filter disk which is held onto the sensor with
a rubber retaining boot. The charcoal filter disk scrubs out interfering gases to which the
CO sensor responds such as H
2
S and certain hydrocarbons. The 65-2423RK-05 explosion-
proof H
2
S detector includes a rubber boot and a spacer which help ensure that the sensor
remains plugged into the detector housing body. The 65-2495RK non-explosion-proof H
2
S
detector includes an adhesive backed gasket inside the detector housing cap which helps
ensure that the sensor remains plugged into the detector housing body.
Figure 4: 65-2433RK-05 CO Detector, CSA
Detector Housing Cap
Plug-In Oxygen Sensor
Detector Housing Body
Cap Gasket
Hydrophobic Membrane
Detector Housing
Cap Gasket
CO Sensor
Detector Housing
Cap
Rubber Boot
w/Charcoal Filter Disk