However, gas detectors have been widely used in […]
However, gas detectors have been widely used in the petrochemical industry. At that time, the detector consisted of only one sensor. It can only perform simple detection, output millivolt-level voltage signals, signal processing circuits in the alarm controller section, and sensor output signals. Due to the great influence of the transmission cable, the detector and the alarm controller must be used one-to-one in a fixed manner. After the installation on site, the calibration must be completely re-adjusted. The commissioning and maintenance workload is very large, and the advantage is that the price is very low.
After entering the 1990s, the signal processing circuit is placed in the explosion-proof housing of the detector and outputs a standard current signal of 4~20MA. This allows the detector to be less affected by the transmission cable and can be directly connected to the DCS system. At present, most domestic manufacturers use this product to detect gases.
In the mid-to-late 1990s, foreign similar products included detectors with on-site digital display of gas concentration and adjustment parameters using magnetic bars or far infrared rays. There are only a few joint ventures in the country that produce this product.
Due to the popularity of computer technology in the industrial field, the standardization process of instrument signals has been promoted. Combustible gas transmitters and alarms are increasingly being influenced by standardization and intelligence.
The flammable gas detector developed from the early flammable gas detector to the current output standard signal has successfully solved many problems such as short transmission distance and difficult modulation caused by the non-standard transmission signal.