The Model 420 is a membrane covered galvanic oxygen probe with built-in two-wire 4-20 mA transmitter. The probe is connected to a DC supply and draws a current of between 4 and 20 mA corresponding to the oxygen concentration.
There are only two wires to connect, and there is no limit to cable length. The output signal is galvanically isolated from the built-in electronics and the process fluid. Interference between the Model 420 and other equipment can never occur!
The OxyGuard Model 420 can therefore be connected directly to a wide range of equipment that can accept a 4-20 mA input, such as alarms, indicators, controllers, recorders, PLC’s, PC systems with A/D input etc.
The Model 420 can also be used to measure gaseous oxygen concentration.