New PXI-based strain gauge simulator

Simulating a resistive strain gauge can be a difficult task; the change in resistance value caused by applying stress to a strain gauge is extremely small (typically 0.1 per cent) and requires very fine control of the resistance value. Many users resort to in-house methods of simulation that are hard to support and lack traceability, or they have to adapt commercial products that provide limited performance. Pickering Interfaces has made this task simpler with the introduction of what is believed to be the first commercially available strain gauge simulator in PXI.

There are six channels of strain gauge simulation with high simulation accuracy and performance. Each channel provides a full bridge circuit with very fine resistance control of better than 2milliohm in one bridge arm, allowing the 40-265 to emulate the operation of a strain gauge bridge circuit. The bridge can be excited by a fixed internal supply or by independent external bridge voltage sources, permitting direct connection to strain gauge measuring systems.

The 40-265 is controlled by simple resistance calls to the variable bridge resistor and each channel has a stored resistance value at which the bridge is balanced. Users can simply set the bridge to the balance point and then offset the bridge using the very fine control of resistance provided by the 40-265 to simulate applied strain. The bridge output voltage is provided directly to the user connector. The 40-265 permits the user to simulate an open connection for fault simulation.

Simple, dependable and high-performance

A calibration port provides a simple way of using a DMM to monitor the channels and to support in-house calibration of the strain gauge simulator with an external DMM.

David Owen, Business Development Manager for Pickering Interfaces commented: "For the first time users have a simple way of simulating the characteristics of a strain gauge when testing control systems, without the complexity of custom designs. The 40-265 provides a remarkably stable and high performance solution with high channel density in a form/factor that is easy to use. The module can be used in PXI or in LXI systems through the use of Pickering's modular LXI chassis, making it suited for use in the most popular test environments".

Pricing and availability information is available at www.pickeringtest.com.