Focus on Pressure
Automatic pressure calibrator
Pressure instrument calibration requires accuracy and repeatability. The 729 automatic pressure calibrator automatically generates precise test pressures, compensates for leaks, and automatically documents the pressure calibration process to help meet compliance and regulatory requirements.
With the portable 729, technicians input a target pressure, and the calibrator automatically pumps to the desired set point while the internal fine adjustment control stabilizes the pressure at the requested value. The device has automatic pressure generation and control for multiple tests to 300 psi (20 bar, 2 MPa). Calibration documentation is done using defined templates for transmitters and switches. Input the starting and ending test pressures and number of test points, and the calibrator documents the applied pressure, measured mA, and percentage error for each test point. The bright graphical display flags test results that are out of tolerance in red.
Pressure and vacuum gauges
The adjustable red/green zone dial face on the pressure and vacuum gauges cues when a system is out of green-zone operation. Dial-face adjustability allows companies to apply a unified visual warning system across a range of processes for quicker recognition of issues. Red indicator bands on the high and low end of the green zone delineate the upper and lower boundaries of safe operation for each pressure or vacuum system where the gauge is applied. The red band, covering the entire out-of-specification zone on the dial face, makes deviations from acceptable conditions visible. This type of monitoring/warning system is suitable for all personnel, including those new to the plant.
Digital pressure sensors
TEPS-series sensors are available with measuring ranges from vacuum up to 5,800 psig. Selectable engineering units, such as bar, mbar, kPa, MPa, inches of water column, and inches of mercury, can be shown on the digital display. The series withstands extreme shock and vibration and incorporates a combination of overpressure, burst pressure, and stability for each measuring range.
Encased in a stainless-steel housing, the EPS-series sensors have an IP67 ingress protection rating, and achieve their atmospheric pressure reference at the four-pin M12 electrical connection. The standard ¼” NPT male process connection allows direct installation without requiring extra fittings. With no moving parts, such as pistons or springs, that can stick or break, two solid-state switch outputs are an alternative to mechanical pressure switches. On certain models, the second output can be configured as a scalable analog signal, turning the unit into a combination pressure switch and transmitter. The built-in two-color digital display indicates the measured pressure and switch set points.
The company added a 1–5 VDC low power output option to the PMP71 pressure transmitter that draws only 17 milliwatts of power at 9 V. This draw makes the PMP71 suited for battery- and solar-powered applications, such as remote oil and gas wellheads, offshore platforms, or pumping stations where low power consumption is critical.
The PMP71 measures absolute and gauge pressure of gas, steam, or liquid and has built-in algorithms to calculate level, volume, and mass of liquids. Measuring spans are available in ranges from –6 psi to +6 psi up to –15 psi to 10,500 psi. For safe operation at process temperatures up to 752°F, it has a piezoresistive measuring cell and a metallic welded process isolating diaphragm. The PMP71 has ATEX, FM, CSA, NEPSI, and IECEx approvals and is suitable for use in up to SIL 3 hazardous applications. The voltage output version is available with the CSA C/US XP approval in North America.