The microprocessor-based Baker Hughes XMTC Panametrics Thermal Conductivity Binary Gas Transmitter from HMA INSTRUMENTATION is a compact, rugged online thermal conductivity transmitter that measures the concentration of binary gas mixtures containing hydrogen, carbon dioxide, methane or helium. The analyser also combines computer-enhanced signal measurement with fast-response software, real-time error detection, and digital communication via an RS232 or RS485 interface.

A sample system is mandatory for use with the BH XMTC Panametrics Thermal Conductivity Binary Gas Transmitter from HMA INSTRUMENTATION. The design of the sample system depends on the conditions of the sample gas and the application requirements. In general, a sample system must deliver a clean, representative to the XMTC at a temperature, pressure, and flow rate that are within acceptable limits. Standard XMTC sample conditions are a temperature of under 50°C, with a flow rate of 250 cc/min at atmospheric pressure. A higher temperature option is also available.

Sample and reference gases are in contact with constant current thermistors. Heat is transferred from 150 °C thermistor to 55 °C cell wall at a rate proportional to the thermal conductivity of the gas mixture.

Thermistors are two legs of a Wheatstone bridge circuit. The resistance difference between RT1 and RT2 yields a mV signal across the inside of the Wheatstone bridge. Linear relationship between bridge voltage and gas composition.

Decision Making Factors:

• % level gases in Hydrogen
• General purpose to ATEX/IECEX Zone 1 and Class 1, Division 1
• Auto-calibration when used with XDP display
• Ultra-stable calibration and no moving parts result in infrequent maintenance