Panel-mounting sensors perform under pressure

An American Sensor Technologies product story

Edited by the Engineeringtalk editorial team Apr 29, 2005

Model AST4200 pressure sensors are designed to provide a hermetic seal against the media without the use of adapters.

Pressure transducers form a critical function in today's closed-loop systems, providing data for safety, control and alarm functions encountered in typical industrial applications such as heating boilers, HVAC/R, gas correctors, compressors, test stands, fire suppression equipment and power generation.

These sensors measure a wide range of benign and corrosive media, with temperatures ranging from -56 to +150C.

Systems integrators and panel builders have traditionally relied on sensors mounted to bulkhead fittings in order to form of pressure connection for pressure measurements.

This meant that in a typical panel, the sensor was mounted inside to a panel-mounted bulkhead fitting and sealed by means of Teflon tape or face O-ring and requires an additional connection between the bulkhead fitting and the hose.

The seals between the sensor, bulkhead fitting, and the hose are critical and, if not formed correctly, can lead to leaks and eventual failure of the system, particularly in systems that handle water, steam, corrosive gases and liquids.

Using panel-mount pressure sensors, such as American Sensor Technologies (AST) Model AST4200, can overcome this problem as these sensors were designed to provide a hermetic seal against the media without the use of adapters.

The unique one-piece bulkhead design of the AST4200 mounts through the panel to keep hazardous media out of the control box.

Secondly, the solid one-piece 17-4PH or 316L high strength stainless steel design is free of welds, internal O-rings or fluid-filled cavities, making it ideal for applications that require high proof and burst pressures.

The sensor requires a minimal mounting configuration that utilises a standard panel punch.

A locknut is used to hold the sensor to the panel, and leaves room for a gasket to be used.

Two wrench flats on the nose of the sensor allow the user to tighten the external pressure tubing to the sensor without turning the part.

Units offer outputs of 10mV/V, 4-20mA or 1-5V.

Units provide long life and resistance to media corrosion as well as superb over range and burst protection.

In addition to using strain gauge technology, the AST4200 offers wetted material such as titanium and nickel alloys with its own-patented Krystal Bond technology to produce strain gauge sensors that yield a high output with low thermal errors.

The AST4200 pressure sensors provide gauge, sealed gauge or compound gauge pressure measurement in ranges up to 690bar.

Sensors are calibrated and temperature compensated to ensure stability over specified ranges.

Units offer accuracy of better than +0.5% BFSL at 25C and long-term stability of +0.25% full-scale output per annum.

Exhibiting excellent resistance to high vibration, shock and temperature extremes, and high levels of EMI/RFI filtration, units are able to perform in a variety of demanding environments.