I/P Converters

I/P signal converters are used in industrial automation to convert a DC electrical signal into a proportional pneumatic output pressure. Typical applications include pneumatic actuators, valve positioners, control valves, and field instruments where a command signal from a PLC, DCS, or electronic controller must be interfaced with an instrument air system.

This category includes the OMC PC13, PC15, and PC18 converters. The PC13 and PC15 convert a DC input signal to pneumatic output ranges of 3–15, 2–18, 2–20, or 4–30 psi. The PC13 is supplied in an ABS enclosure rated IP20 for panel mounting. The PC15 is intended for field mounting and is also available, on request, in an intrinsically safe version certified to ATEX 2014/34/EU, II 1 G Ex ia IIC T6/T5 Ga.

The OMC PC18 is used where higher pneumatic output capacity is required, such as with larger diaphragm or piston actuators, or in applications where control pressure must reach up to 8 bar. It is also available in an optional ATEX version, II 1 G Ex ia IIC T6/T5 Ga, for installation in hazardous gas atmospheres.

Selection should be based on the electrical input signal, required output pressure range, available air flow, supply pressure, conversion linearity, response time, mounting position, enclosure protection, and any requirement for intrinsically safe installation. Instrument air quality is a critical operating factor: moisture, oil carryover, particulate contamination, and unstable supply pressure directly affect output accuracy, nozzle-flapper stability, actuator response, and control loop performance. In valve service, output pressure capacity must also be checked against actuator spring range, bench set, diaphragm area, stroking time, and any positioner or volume booster installed in the circuit.