D12Ex-IR Infrared Gas Transmitter Description

Model D12Ex-IR is a versatile infrared system used primarily for the detection of combustible levels of methane or other hydrocarbons. It may also be used for monitoring CO₂ levels, either in ppm or percent levels.

The D12Ex-IR employs a compact infrared sensor for monitoring without the poisoning problems found with catalytic bead sensors. While catalytic bead sensors offer reliable service, the presence of silicon vapors, hydrogen sulfide, and halogenated hydrocarbons can degrade sensor performance. Infrared sensing is not susceptible to these types of problems. This means longer and more stable sensor life.

“Smart” IR sensors are used in the D12. These sensors come factory calibrated for methane, propane, and butane. In addition, cross sensitivity factors for many different hydrocarbons are provided, allowing for maximum application flexibility. Sensors are also available for monitoring percent levels of hydrocarbons.

IR sensors are also available for CO₂ monitoring. Two sensors are available, one for ranges of 0-1000 ppm up to 0-5% and another for ranges of 0-5% up to 0-50%.

D12Ex-IR Gas transmitters are designed for operation in hazardous areas. Transmitters are certified for installation in Class 1, Division 1, Groups B, C & D locations and are certified flameproof to both IEC and ATEX specifications.

Digital communications are available with either HART™ or MODBUS™ protocol. The HART™ protocol supports the Universal and Common Practice Commands at 1200 baud using the Bell 202 FSK modem standard. The MODBUS™ protocol supports 9600 baud access to concentration and status information, and supports alarm setup and many other functions on either RS485 or RS232 (software selectable).