Research On The New Calibrating System Of Coal Mine Gas Sensors

Coal mine gas sensor is the important security in coal mine production, and There will be major industrial accidents without timely warning from coal mine gas sensor under the situation of excessive harmful gases. Therefore, Our country has regulations about periodic calibrating on the coal mine gas sensor.The calibrating system of coal mine gas sensors detects output signals of coal mine gas sensors in the normal work, and automatic calculates coal mine gas sensors'stability of displayed value, basic error, response time and the function of alarm, based on a series of industry standards for coal mine gas sensors from the State Administration of Work Safety. It can easily and quickly complete the work of calibrating coal mine gas sensors, and guarantee the security in coal mine production.Based on the study of principle in calibrating coal mine gas sensors, This paper invented slave device of the calibrating system on ARM7,and host PC program of the calibrating system on VC++6.0.This paper originally proposed the way and program of computing the core parameters too.The slave device of the calibrating system was constituted by hardware and software. Hardware circuit was divided into three parts: Power supply part, Signal processing part and Master part. Each part can also be contained different circuits. Power supply part was divided into Sensor power supply(DC9～24V adjustable), Signal acquisition chip power supply (DC9V), Main circuit power supply (DC5V), and The master chip and memory chip power supply (DC3.3V). Signal processing part was contained by the signal Acquisition circuit, the signal Processing circuit, the signal Storage circuit and signal Transmission circuit. Master part had two circuits: both Master chip circuit and Controlled gate circuit. The program of the slave device was programmed under ADS(ARM Developer Suit)that was matched with the main chip LPC2131.The host PC program of the calibrating system contained five parts. They were Communication management program, Data storage and link program, Human-machine program, and Conclusions operation program. The part of the conclusions operation program was described deeply in the separate chapter because of innovative.At present, The calibrating system of coal mine gas sensors is testing in laboratory. The results shows that this calibrating system has powerful data processing capability, precise calibration accuracy, strong anti-interference. This paper provides a viable new way of automatic calibration of the coal mine gas sensors.