VQ500 gas sensors series
The VQ500 Series from SGX Sensortech is a complete range of miniature, fully certified, flameproof sensor heads containing a high quality, low power pellistor pair that is optimized for the detection of combustible gases or % volume gases in thermal conductivity mode. They have an outline identical to modern miniature electrochemical cells and are ideally suited for use in portable instruments.
Within the VQ500 series there are specific sensors that are able to detect most combustible gases and vapours and ammonia (VQ547TS) at LEL levels. The thermal conductivity version (VQ546M or VQ546MR) will detect most gases at % volume concentrations which have thermal conductivities different from that of air. The VQ548ZD/W and VQ549ZD/W variants performed a temperature test during its manufacture to confirm that the temperature performance meets the datasheet ensuring compliance to the various mining performance standards (Group 1). The VQ548ZD-S variant has extra burn-in for enhanced stability. The LEL series VQ548 and VQ549 have protection to minimize silicone poisoning and areH2S and shock resistant.
The new member of the VQ548 family (VQ548MP) has a proprietary MEMS pellistor design with the same safety features (flame proof, intrinsically safe, poison, H2S and shock resistance) as the classical VQ548 series, but the power needed to operate the VQ548MP has been further reduced. In continuous mode it requires only half of the power needed for a normal VQ548, and because of the MEMS design, the sensor can also be powered using a cycled operation mode with a duty cycle as aggressive as 10 % on / 90 % off. This saves even more energy, and in power saving optimal mode the element requires less than 20 % of the power required for a standard VQ500 element.