Detcon IR-542 - Manual (Page 4)

3.0.2 Microprocessor Control Circuit
The control circuit is microprocessor based and is packaged as a plug-in f ield replaceable module, facilitating easy
replacement and minimum down time. Circuit functions include a basic sensor pre-amplif ier, sensor temperature
measurement, on-board power supplies, microprocessor, back-lit alpha numeric display, fault and calibration status
LED indicators, magnetic programming switches, and a linear 4-20 mA DC output.
3.0.3 Base Connector Board
The base connector board is mounted in the explosion proof enclosure and includes: the mating connector for the
control circuit, reverse input and secondary transient suppression, input f ilter, and lugless terminals for f ield wiring.
Detcon Model IR-540/IR-542 Carbon Dioxide Sensor PG.4
detcon inc.
Program Switch #2
FLT CAL
MicroSafe™ CO2 Gas Sensor
HOUSTON, TEXAS
PGM 2
PGM 1
MODEL IR-540
CONTRAST
Fault & Cal LEDs
Program Switch #1
Menu Driven Display
Plug-in Microprocessor Control Circuit
Display Contrast Adjust
Porous Membrane
Optical Filter
Active Detector
Lamp
Reference Detector
Optical Sample Gas Chamber
Optical Filter
CO2 CO2
BLU
YEL
BLK
WHT
mA
VDC Power In
4-20 mA Output
BRN
RED
Sensor
Base Connector Board