Honeywell analytics supplies combustible gas sensor with explosion proof sensor assembly. Honeywell analytics products are manufactured in accordance with ul 2034, bs 7860:1996, and en-50291:2001 and iso 9001:2000. The 705 combustible gas sensor with explosion proof sensor assembly is a low cost sensor, fitted with sieger poison-resistant combustible gas detection elements. Fully encapsulated, it is designed for use in hazardous locations. The sensor is electro-catalytic and consists of 2 beads of refractory oxide formed on a fine platinum wire coil. The active bead is coated with a catalyst material, whilst the reference bead is glass coated.
In the presence of gas, the catalyst coated bead promotes the oxidation of the gas, causing it to heat up increasing electrical resistance. This change of resistance, relative to the reference bead can be measured and is in direct proportion to the concentration of combustible gas. The signal is converted to an analog output for direct display on a companion control card as percent lel [lower explosive limit].