The passive isolator’s safety functionality is the highly precise, linear transmission of 4-20 mA signals with a low transmission error of 0.08% full scale. A high level of functional safety can be achieved even in single-channel structure and without diagnostics. For instance, sensors and actuators in safety circuits can be connected directly, requiring no elaborate evaluation equipment for redundant structures.

The isolator’s robust design ensures a high degree of availability. Knick says that thanks to loop-powered operation, it contains fewer parts than devices with an auxiliary power unit and the total failure rate is decreased. Furthermore, it is mechanically stable, approved for marine applications, resistant against electromagnetic interferences, and has protection against electric shocks to 600V AC/DC through reinforced insulation.

The test voltage during routine testing is 5.4kV AC. ProLine P 22400 is suitable for ambient temperatures between -40 and 85 °C. Knick provide a five-year warranty for all ProLine devices.