When you want to measure motor torque, a DC motor torque transducer is the way to do it. DC-operated, these devices provide an analog output of +/-5V (optionally, +/-10V). Fully bidirectional, a DC motor torquemeter gives accurate and repeatable measurement of the torsion delivered by a motor.
Strain Gauge Torque Measurement
An S. Himmelstein and Company DC motor torque sensor measures torsion with strain gauges embedded in the shaft. These thin, highly specialized wires are mounted at 45 degrees to the shaft axis. As the shaft twists, the strain gauge is stretched or compressed, depending on its orientation. Extension and compression both slightly alter the wire's electrical resistance. In a single gauge, this change is hard to detect, but coupling four into a Wheatstone bridge will make the effect observable.
Shafts rotate, so the second problem is providing excitation to the strain gauges and retrieving the resulting electrical signals. Our torquemeters accomplish this through a rotary transformer. When used with high-quality signal conditioning equipment, this results in precise measurement of torque in the shaft while avoiding the problems inherent in slip ring designs.
A DC-operated torque transducer operates on 10.5 to 24 Vdc supply (optionally, 18 to 24 Vdc). Output is +5 Vdc for clockwise torque and -5 Vdc for counterclockwise. (Specify Option L for +/-10 Vdc output).
Voltage is output at two frequencies simultaneously: dc to 1 Hz (the low-frequency output) and dc to 500 Hz (high-frequency output).
Flanged and Shaft-End Models
For application flexibility, DC motor torquemeters are offered in flanged and shaft-end models. Shaft-end models may be floated or foot-mounted and work well in many applications. For high axial loads, flanged torquemeters are preferred. A second advantage of flanged models is that they take less space (but must be installed floating).
DC Motor Torquemeter Applications
The main use of a DC motor torque meter is measuring torque produced by electric, pneumatic and hydraulic motors. These motors are used in process equipment such as mixers, emulsifiers and extruders. They are also seen in winding equipment, rolling mills, conveyors and grinders. Torque measurement yields information on processing conditions and indicates when maintenance is due. Thus, a DC motor torque sensor can help protect against breakdowns and unplanned downtime.
Choosing a DC Motor Torquemeter
Our non-contact DC-operated torquemeters are produced with 200%, 400% and 1,000% overload ratings. (Smaller models employ a titanium shaft rather than the 15-5PH stainless or larger models.)
Maximum torque for the analog torque meter is 4,000,000 lbf-in. Peak speed is 15,000 rpm with High Speed models operating up to 25,000 rpm.
Torque Measurement Specialists
We've built robust, high-precision torque measurement systems, including DC analog rotary torque transducers, since 1960. Our DC motor torquemeters perform reliably in the toughest environments and offer an unmatched combination of performance and price. Installation is straightforward and, should after-sales support be needed, our service is second-to-none. When you need a DC motor torque transducer, contact S. Himmelstein and Company.