IP81: Explosion Proof Current to Pressure Transducer


The IP81 explosion proof transducer delivers reliable high performance for the toughest applications in the most hazardous environments. Its NEMA 4X (IP65) housing is designed for both intrinsically safe and explosion proof operation.

Advanced circuitry includes electronic feedback control for superior vibration protection and highly accurate output. With flow rates up to 12 SCFM (20m3/hr), the IP81 has the muscle to drive large valves and actuators.

It is very economical to operate, consuming only 0.05 SCFM (0.11m3/hr), which is especially important in natural gas applications. An optional mounting kit lets you mount it directly on a valve, wall, panel, or 2” pipe.

Easy access Zero and Span adjustments make bench or field calibration quick and easy. For operating versatility, you can choose direct, reverse, and split range modes. A piezoelectric bimorph actuator and surface mounted electronics are conveniently mounted on a removable control manifold that allows easy maintenance.

Transducer Operation

The transducer uses a nozzle to control pilot pressure to an integral volume booster. The resulting output pressure is measured by a pressure sensor, which in turn provides a feedback signal to the control circuitry.

The feedback circuit compares this signal to the input signal and self corrects as necessary, minimizing the effects of vibration, position, temperature and supply pressure.

The current signal flows to the piezo actuator causing it to bend toward the nozzle, which restricts the flow of air through the nozzle and creates back pressure in the pilot pressure chamber. This back pressure acts as a signal pressure which in turn controls the pressure at the output.


  • Compact size
  • Explosion proof
  • Intrinsically safe
  • Mount in any orientation
  • Easy wiring
  • Accuracy ±0.10% of span
  • RFI/EMI protected
  • Supply pressures to 100 psig
  • NEMA 4X (IP65)
Specification IP81
Input 4-20mA
Output 3-15psi, 3-27psi, 6-30psi
Maximum Supply Pressure 100psi
Accuracy ±0.1% of span
Loop Load 10.0VDC
Connections/Mounting 1/2″ NPT Conduit/Panel Mount
Air Consumption 0.045scfm
Flow Capacity 4.0scfm
Operating Temperature -40 to +160°F
Agency Approvals FM, CSA, CE
Operational Modes Field selectable: direct, reverse, or split range
DIN Rail Mounting Optional
Manifold Mounting Optional
Warranty 18 months