RKI Instruments RI-215A - Manual (Page 9)

RI-215A Operator’s Manual Internal Description • 9
LCD
The LCD is mounted to the printed circuit board. The LCD shows the current gas reading
of the RI-215A’s target gas. The LCD also shows operational messages when the RI-215A
exceeds its full scale.
IR Gas Detector
The IR detector uses infrared light and an infrared sensor to detect CO
2
. A small infrared
light source is located in the detector. As CO
2
enters the detector, it absorbs infrared light
in a characteristic way as the concentration increases. The infrared sensor detects this
change in infrared light and the unit converts this to a gas concentration.
Fuse
One extractor-type fuse protects the AC line circuitry from short circuit or overload. The
fuse is rated at 0. 5A, 125 V. See “Parts List” on page 23.