Industrial Fixed Gas Detector RS485 Signal Output 4 In 1 EX O2 CO H2S Gas Tester Detector Item Type: Industrial Fixed Gas Detector Material: Die Cast Aluminum Detection Range: EX 0-100% LEL, O2 0-30% VOL, CO 0-500PPM, H2S 0-100PPM Display: LED Liquid Crystal Display Detection Accuracy: ±3%F.S LCD Display: Measured Gas Name, Real Time Value, 50 Segment Bar Graph Displaying Real Time Gas Concentration, Gas Full Scale, Gas Internal Parameters Working Environment Temperature: -20-50℃ Working Environment Humidity: 10-95%RH, Non Condensing Signal Output: 1. 4 To 20mA Signal: Standard 12 Bit Accuracy 4 To 20mA Output Chip, Transmission Distance: 1Km. 2. RS485 Signal: Standard RTU Protocol, Transmission Distance: 1Km. Remote Control Battery: CR2025 Button Battery x 1 (Shipped Without Battery)