To capture gas flows away from the source of the leakage rate, measured by sampling at high speed, thus there is a dilution of the surrounding air. Accurate sample flow rate and natural gas concentration allow leak rates to have calculation. The instrument automatically compensates for the difference in gas content between the sample and the ambient air, thus ensuring an accurate leak rate calculation.
A small-sized optical sensor (form factor 20mm) with a wide temperature range of – 40. . .+60 °C at a low cost measured the concentration of natural gas. The main difference from most optical sensors is the replacement of an incandescent micro-lamp emitter with a semiconductor LED emitter and a pyroelectric photodetector receiver with a photodiode receiver with an integrated spectral filter. This technique has improved reliability and significant reductions in sensor power consumption, which is essential in battery-powered systems.
To extend the accuracy of measurements on high amounts of leakage, we are using our proprietary patented technology, Displaced Oxygen Correction. The measuring system has an additional sensor that indicates the volumetric oxygen content. During system purging, the reading came checked with 20.9% O2. According to its corrected tasks, the natural gas content in the stream, thus the influences of high-order hydrocarbon impurities, was eliminated. At low gas concentrations in the sample, reducing the sampling rate to ensure higher measurement accuracy was now possible.
The sampler found installation in a case secured to the specially designed harness, leaving the operator’s hands free to use when climbing stairs and descending into sewers. There became no apparent use for the harness with the sampler. The sampler is controlled wirelessly using an Android phone (version 6.0 or higher) that displays technical information and supervises the Gas Flow Meter sampler. Reception distance up to 5 meters. GFM 2.0 has meager energy consumption allowing uninterrupted measurements for about 14-14 hours.
GFM 2.0 HazLoc IS Evaluation, Testing and Certification is currently underway by UL LLC