Product Specification

OEM 4-20mA Transmitter for NDIR Gas Sensors
(Methane/Carbon dioxide)

Cirius X OEM 4-20mA Transmitter for NDIR Gas Sensors Description and Operation
The Cirius X OEM 4-20mA transmitter is an extremely flexible transmitter for NDIR gas sensors providing a robust 12 bit linear 4-20mA selectable source/sink output in response to signals from standard NDIR gas sensors. All sensor driving, signal extraction and linearisation is performed on board with calibration and configuration accessed by a menu driven sequence using 3 pushbuttons or via the RS232 port. The 2-line LCD display shows the gas concentration and units under normal operation, fault diagnostics under fault conditions and interactive text under pushbutton operation for calibration. The pushbuttons are disabled if the display is removed, enabling tamper-proof running. Sensor connections to the Cirius X are made by 3-way and 4-way crimp EH connectors, segregating the sensor supply from the signal lines. Connections for the input power and 4-20mA signal are via screw terminals and an earth spade terminal is provided along with an earth bonding pad for ease of earth connections.

Cirius X OEM 4-20mA Transmitter for NDIR Gas Sensors Features
? Wide power supply voltage range
? Robust linear 12 bit link selectable 4-20mA source/sink output stage
? Fully configurable for a wide range of NDIR gas sensors
? Comprehensive RS232 communications
? Extensive fault monitoring
? Input power and output signal polarity protection
? Detachable 2 line LCD display with switchable backlight
? Menu driven pushbutton calibration
? Small size
? Designed for fixed head systems
? Optional plug in Hall Effect switch panel for "through the glass" calibration
? Wide operating temperature range
? Earth contact pad and earth spade terminal
? Designed in accordance with the SIL specification

Cirius X OEM 4-20mA Transmitter for NDIR Gas Sensors Outline Details
All dimensions in millimetres (±0.1mm unless noted)


Cirius X OEM 4-20mA transmitter Performance 
Unless otherwise stated all data was taken using: 
Supply voltage of 24V. Ambient temperature (between 20°C and 25°C). Ambient pressure (between 995 hPa and 1020 hPa). Cirius 1 hydrocarbon IR sensor connected and powered by the circuit.