Monthly Archives: August 2016

The Operation of, and Benefits Provided by, Our Variable Reluctance Pressure Transducer

All pressure transducers sense pressure from the outside mechanically and produce an electrical signal in response to these changes.

When it comes to the variable reluctance pressure transducer, a sensing diaphragm changes position with pressure, inductively changing the impedance of the two sensing coils. This change produces an electrical signal.

As the potential user of pressure transducers, you need to know what type of unit is best suited for your particular application. At Validyne Engineering, we can point you in the right direction to find the pressure transducer that matches your particular needs.

Let’s look at the Variable Reluctance Pressure Transducer

The VR pressure transducers we offer at Validyne Engineering consist of a flat diaphragm (magnetically permeable) supported between two coils. A magnetic field is produced between the coils and the diaphragm when an AC excitation is applied. The opposition to the lines of flux (called the reluctance) is determined by the air gap present between the two coils and the diaphragm. The coils are wired electrically as an inductive half-bridge.

In this arrangement, an AC signal is produced in direct proportion to the deflection of the diaphragm. This is how it works: with the diaphragm in a relaxed, or ‘zero’ state, position, the magnetic field between coil 1 and the diaphragm is balanced with the magnetic field between coil 2 and the diaphragm. So there is a gap produced depending on the position of the diaphragm and each coil. This produces an AC output voltage.

Particular benefits provided by the variable reluctance pressure transducer include:

  • Measurement of very low pressures
  • Low power consumption
  • Wet/Wet differential measurements
  • Suited for high levels of vibration
  • Fast Dynamic Response

The variable reluctance transducers we offer at Validyne Engineering have a track record of accuracy and reliability in various environments. Allow our team to guide you in selecting the best pressure transducer(s) for your particular application.

A brief review of the PS309 and PS409 Pressure Manometers offered by Validyne Engineering

Both the PS309 and PS409 pressure manometers offered by Validyne Engineering feature lightweight construction, absolute differential, and gauge ranges of 0.08 psi to 3200 psi FS. All surfaces that contact pressure media are 410 stainless steel in both units. There are, however, some differences. Let’s briefly review each manometer and cover some features and capabilities of each.

PS309 Pressure Manometer

pressure manometerAs a totally self-contained pressure manometer, the PS309 is a portable unit that comes in gauge, absolute, and differential ranges. It offers a front panel liquid crystal digital display, as well as a 2 VDC analog output designed for remote recording or control.

For portable operations, the PS309 features a 3.5 digit LCD and battery pack (6-1.5V penlight cells), a solid-state electronics module, and integrated VR transducer. All surfaces that contact the pressure media are made from all corrosion resistant materials. It has ultra-low volumetric displacement with full-scale pressure exertion as well as very low internal cavity volumes.

The unit includes the capacity for individual meter scaling adjustments and, through easy front panel adjustment, decimal point selection for the display is user-programmable.

An optional feature of the PS309 is switch-selected Pressure and Flow operating modes. Each mode offers separate 2 VDC analog outputs and individual scaling adjustments.

PS409 Pressure Manometer

pressure manometerDesigned for installation in rack-mount panels in laboratory and industrial applications, the PS409 pressure manometer we offer at Validyne Engineering is a self-contained digital indicator and sensor. It is ideal where accurate low-pressure readings are needed. The unit includes an integral VR transducer and easy-to-read 0.5 inch high x 4.5 digit LED display. It also offers a temperature range of 0ºF to 160ºF.

Digital Indicator of the PS409

The digital indicator offers read-outs in 3 different engineering units: PSI, In. H2O and In. Hg, which can be selected by the user from front panel buttons. Separate internal calibration adjustments for analog output and meter display are also featured.

Pressure Transducer for the PS409

Available in gauge, absolute, and differential versions, the PS409 is built of corrosion-resistant materials at points of contact with pressure media. The PS409 is available in 23 pressure ranges, from 0.08 to 3200 psi FS. The unit can also deliver 5 VDC analog output for remote display, control or recording purposes.

Applications of the PS409 include pneumatic systems, test cell and test panel applications, engine and vehicle test stands, pumps and hydraulic systems, process/product control testing, gas distribution, emission testing, and fuel pressure.

university lab

Introducing the Validyne University Website

Validyne invites you to a closer look at one of our latest projects, the University Validyne website, which will enable us to enhance our engineering program and better serve our customers by partnering with university lab programs. Learn more about a history of partnerships with universities, as well as have the chance to see first hard which products and services are currently popular in the university labs.

About Validyne Website


Validyne Engineering is a leading manufacturer of variable reluctance pressure transducers as well as pressure sensors and data acquisition solutions. The University Validyne website will enable our customers in the educational fields to learn more about our impact on the learning environment.

Validyne pressure transducers, pressure sensors, and signal conditioning have been in use in laboratories for graduate and undergraduate students since 1970. Our full scale pressure range of transducers, sensors and vital data acquisition systems are in use in a variety of learning environments including:

  • Fluid Mechanics
  • Biocric Research
  • Mechanical Engineering
  • Civil and Environmental Engineering
  • Mechanical and Aerospace Engineering
  • Geotechnical Engineering

Our products are being used in research labs for numerous case studies and research projects such as:

  • Cryopreservation of human pulmonary tissues
  • Tubing Networks for Full Scale Pressure Measurements
  • Mechanics of Fluids and Transport Processes / Aerodynamics Lab
  • Wind Tunnels

Programs to Meet Changing Needs

Pressure measurements are constantly changing and, in order to keep up, university laboratories need access to pressure transducers whose range can be changed. This is the best choice for laboratories.

Our data acquisition products provide flexibility and accept any sensor inputs including strain gages, Validyne pressure transducers, thermocouples, RTDs, LVDTs, resistances and DC volts in any mix or combination. These products combined with our Easy Sense software and USB interfaces, provide conditioning that can be quickly programmed to meet changing needs.

At Validyne Engineering we are proud to offer our superior products and services to university laboratories. Together with universities, we are building on a future for the engineering field.

university lab

A Closer Look at the USB2250 Data Acquisition

As a leading manufacturer of variable reluctance pressure transducers, we at Validyne Engineering make it our top priority to provide our customers with the latest technological advances. That is why we are pleased to introduce the USB2250 Data Acquisition.

What is a USB2250 Data Acquisition?

usb2250bThe USB2250 is a sensor interface that provides real world data acquisition for your PC through the USB port. Up to 16 different sensor inputs that are accepted by the USB2250 in any mix or combination with no external signal conditioning required.

All in One Configuration via the USB2250 Data Acquisition

When we say that up to 16 sensors are accepted no matter the mix, we mean no additional equipment or configuration is required. Thermocouples, RTDs, strain gages, LVDTs, potentiometers, VR sensors and low-level DC voltages are all wired directly to the terminal block..
In addition, the USB2250 Data Acquisition features 10 full scale input ranges from ±20 mV to ±10.24V full scale all with 16 bits of resolution. There is zero offset correction for low-level measurements. The USB2250 Data Acquisition also provides polynomial linearization for thermocouples and RTD’s. It produces a floating-point value directly in engineering units.

Included Software

Data Acquisition

Software includes a GUI configuration utility that gives the user the opportunity to set sensor type, gain range, channel, and other parameters. Easy Sense 2250 data acquisition software is included with Graphic Capabilities and Trigger Functionality included in the Premium Easy Sense version.

A LabVIEW VI is available for seamless integration to your existing software setup.

Exciting Uses and Possibilities

Data acquisition is the process of measuring electrical or physical phenomenon like voltage, current, pressure, temperature, or position with a computer. The USB2250 is a vital tool for those working in the oil, automotive, or medical industries and many more!

At Validyne, we work hard to provide our customers with the best equipment experience no matter where they operate. Providing equipment like the USB2250 not only makes the job easier, but is a more cost effective solution for sensor inputs to a PC.