The gas transmitter ADOS LCTR 903 is suitable for the detection of combustible gases, for example hydrogen, methane (natural gas) or propane / butane (LPG) in air in the LEL region.
Two transmitter versions with different output signals are available:
- 3-wire 4–20 mA
- 4-wire LON® (LCTR 404)
Three measuring principles are available:
- VQ
- TGS
- IR
Fields of Application
Gas fired boiler systems
Gas distribution station
Gas transfer station
Battery charging station
The TGS sensor
The TGS sensor contains a semiconductor sensor,
which is constructed on SnO2 -sintered N-substrate.
When combustible or reducing gases are absorbed by the surface of the sensor, the concentration of the test gas is determined by the change in conductivity.
The VQ sensor
The head of the VQ sensor functions on the principle of heat reaction. When combustible or reducing gases or vapours come in contact with the measuring element, they are subjected to catalytic combustion, which causes a rise in temperature. This rise causes a change in the resistance of the measuring element which is used as a measure of the component of gas being tested. The inert element is for compensating the temperature and conductivity of the test gas.