Introduction: QB2000 single channel co alarm controller is the single-point supervisory control gas alarming system designed and produced by our company. It is consisted of the gas-detecting main machine and the gas detector and it is used to detect the density of the flammable gas, oxygen, or poisonous gas in the working environment. This system adopts 32 digit embedded micro processor as control unit, high-performing catalytic air-sensitive element or high-precision imported electrochemical sensor as detector which has high sensitivity and quick response. When the detected gas density in the air reaches or exceeds the preset value, the controller will give out audio-visual alarm immediately to remind you take safety precautions and start exhaust, control and start exhaust or other peripheral devices to avoid explosion, fire, toxicosis to protect the safety of life and treasures. This system applies to metallurgy, petrol, petrifaction, chemistry, light industry, coking, municipal administration, gas, pharmaceutical, sewage dealing and many other special industry and field that need proofing for fire, explosion, and toxic gas leakage. Characteristics: ◆ high-performance sensor ◆ the device adopt advanced 32 digit embedded micro controller ◆ display the detected gas density in long distance ◆ high sensitivity, and quick response ◆ customers can set the high and low alarm point by themselves ◆ automatic failure detection for the detector ◆ important operation needs password to avoid operating errors ◆ one 4-20mA signal detector input ◆ one 4-20mA signal output ◆ one RS485 signal output ◆ two alarm points output in linkage, passive switch value 3A Technical Parameters: ◆Detect scope:see the chart ◆ Applicable gas: flammable gas, oxygen, poisonous and harmful gas ◆Error displayed ≤±3% F.S ◆Responded time: T90<30s ◆Display mode: LED digital display ◆Alarm: sound and light alarm ◆Connecting cable: two-wires type detector 2x1.5mm2 length<1000m RVVP Three-wires type detector 3x1.5mm2 length<1000m ◆ Operation condition:-20℃~+50℃; Humidity<90%RH ◆: AC 220V±15%, 50Hz±5% ◆Defending class: IP44 ◆Weight: 18x25x8cm about 2.5kg