To meet the growing demand for precise and reliable compensation resistors used in building transducers such as load cells, Micro-Measurements, a Vishay Precision Group, Inc. (VPG) brand, today announced that its bondable resistors for transducers are now being built on Advanced Sensors Technology and feature high-purity nickel. The LT02 and LT10 series of fixed-value nickel resistors offer tight resistance tolerance and repeatable performance for use in transducer bridge completion circuits.
“A transducer is the generic name given to devices that convert an input stimulus into a measurable signal,” said Ron Zukerman, Micro-Measurements Advanced Sensors manager of marketing and sales. “Precision weighing or force transducers based on strain gage sensors convert the mechanical input of an object, typically the object’s mass or the reaction force caused by a weight applied to the transducer, into a measurable resistance change.”
As the foundation of consistently reliable and precise transducers, Micro-Measurements’ Advanced Sensors bondable nickel resistors are built on a new manufacturing process using state-of-the-art equipment and tooling. This results in a tighter tolerance, better stability, and shorter lead times when compared to conventional manufacturing techniques. Customers who have tested the resistors in transducer products have reported more repeatable test data when compared with previous-generation conventional resistor types.
For the highest accuracy, precision strain-gage-based transducers require compensation for several undesirable influences, most notably the influence of temperature change. These compensations are typically effected using precision resistors of various values and temperature sensitivities. Micro-Measurements offers a complete line of bondable precision resistors for use as transducer compensation elements, including fixed-value and adjustable resistors manufactured using either high- or low-TCR materials.
Micro-Measurements fixed-value resistors, such as the LT02 and LT10 patterns, are typically used for adjusting the full-scale span output with temperature changes, and they are therefore normally produced in high-TCR resistive alloys such as Balco or nickel. Adjustable resistors such as Micro-Measurements’ D01 pattern are ideal for adjusting the room temperature span of a transducer, while dual-sided E01 and H21 patterns can be used to set the initial zero reading. The devices are manufactured using low-TCR alloys such as copper-nickel and nickel-chrome. Dual-sided E01 and H22 patterns are used for compensating the zero reading of the transducer with temperature. Because active temperature compensation is required, these patterns feature high-TCR alloys such as Balco and copper.
Although they are less convenient, but equally effective, low-TCR alloys are also available in small-gage wire, which is cut to the required length and soldered into the transducer Wheatstone bridge circuit with the strain gages.
Further information about Micro-Measurements bondable resistors for transducers is available at www.micro-measurements.com.