Product Name: low concentrations of methane alarm sensor 

 Product Model: GJC4 type 
 Coal safety mark No.: MFB090081 

 Description: 
 The product is a new generation of intelligent methane sensor using standard signal output, with power-off devices and a variety of monitoring systems supporting continuous monitoring of flammable, explosive working environment in the methane concentration. Communication distance, the contact output power, local display, sound and light alarms, infrared remote control adjustment, easy to install and features. 

 Product characteristics and uses: 
 GJC4 low concentration methane sensor (hereinafter referred to as instruments), with embedded micro-controller technology, design and manufacture according to the latest standards, and various types of coal mine safety monitoring system, power outages and other supporting continuous online monitoring of flammable explosive mixture of flammable gas in methane concentration. Has a local display, sound and light alarms, infrared remote control adjust the frequency output signal, digital signal output, power-off control signal output functions and features. 

 How it works: 
 When the instrument placed in the environment, the presence of methane gas, methane gas through the transom of the instrument casing into the gas chamber, gas chamber sensors (carrier of the catalytic components) surface of the flameless combustion, its resistance increases, so that the bridge output and methane proportional to the electrical signal. Signal by the linear amplifier input A / D converters by the microprocessor data processing by the digital display of methane concentration, and the signal output circuit output signal for other devices. The alarm circuit of the instrument by the buzzer, light-emitting diode and drive circuit, when the methane concentration exceeds the alarm set point, the instrument will be audible and visual alarm signal. When the methane concentration exceeds a set power-off point, the instrument will be power-off command signal output; methane concentration exceeds the power point, and only when the methane concentration is reduced to a less complex set isoelectric point, the instrument will lift the power failure The output of the command. The instrument has anti-shock protection measures, when the methane concentration is ≥ 4.00%, the digital tube flashes, the buzzer sounds, instrument automatic black and white components for power protection, and constant output 1000Hz frequency. 

 The main technical indicators: 

 Item Specification 

 Measuring range (CH4) (4)% 
 Basic error (CH4) 0 ~ 1.00> ~ 3.00> 3.00 ~ 4.00 
 ≤ ± 0.1 true value of the true value of ≤ ± 10% ± 0.3 true value 
 Resolution of 0.01% of CH4 
 Response time <20s 
 Working power DC (9 to 24) V/50mA `(intrinsically safe power supply) 
 Output signal (200 to 1000) Hz, and the RS485 (baud rate) 
 Digital signal 2400bps 
 Transmission distance ≥ 2km 
 Alarm method intermittent audible and visual alarm, alarm points continuously adjustable 
 Intensity of sound level ≥ 85dB 
 Explosionproof Type Exibd I 
 Sensor life> 1 year 
 4 LED display 
 Dimensions 270 × 120 × 50mm 
 Weight 1kg 
 Equipment FYF5 mine with a remote control