Instrumentation Monthly Test | Measurement | Control
Exceptional Modularity, Accuracy and High Shock Survivability 
Types 8315A(x) and 8395(x) K-Beam® MEMS technologies provide both temperature stability and low noise for accurate measurement of low-frequency events from DC up to a 1 000 Hz bandwidth. They are ideal for Use in aircraft flight and flutter testing, automotive rough road body motion studies, suspension system tests, railroad or automotive modal and durability testing, among many other applications.
Kistler’s uniaxial 8315A and triaxial 8395 families are based on a high-precision Micro-Electro-Mechanical System (MEMS) variable capacitance accelerometer. Available in six ranges from 2 to 200 g, these sensors incorporate a sensing element with gas damping and internal over-range stops. This enables the accelerometers to survive high shock and acceleration loads in addition to providing precise measurements. Both types have wide operating temperature range of –55°C and 125°C and typical non-linearity and hysteresis of 1% FSO for most ranges. Many input, output, housing and cable options are available to accommodate most applications.
Application Note: Indirect Force Measurement.
For many large force measurement applications, a low cost, indirect strain method is an effective solution. Rather than a bonded strain gauge, a Kistler piezoelectric strain sensor is a popular, cost-effective alternative. The Kistler sensor works by generating a charge signal as strain is applied to the quartz piezoelectric material, which is very stable over a very long life, producing a strain signal that is scaled to a force by applying a sensitivity factor.
A Kistler surface strain sensor is rated IP65 and can be installed quickly and easily using a single M6 hole. In comparison, conventional bonded foil strain gauges require careful and costly installation including: surface preparation, bonding, plus mechanical and moisture protection. This installation work needs to be untaken by a skilled technician.
The location of a strain sensor should be considered carefully. For example on a press, perhaps making car body panels, the reaction force will be taken up by the support structure and the sensor should be located on this structure where the output signal will be the greatest. Sometimes a Finite Element Module of the structure is available to determine the optimum location.
The Kistler strain sensor can offer a simple 0-10V output signal, or can be linked to the Kistler maXYmos monitoring system with its two configurable switches and signal display.
Applications include:
• Force monitoring on C-frames in assembly or pressing machines.
• Quality control of joining processes such as: riveting, clinching & spot welding.
• Safety monitoring, to guard against overload due to tool breakage or tool collision
High speed torque sensor for electric motor & generator testing
As rotational speeds increase, electric motor and generator manufacturers need a reliable and versatile method of measuring torque accurately for both product development and quality control in production and assembly applications. To meet this need, Kistler designed the Type 4503A torque sensor to provide a flexible instrument for use at rotational speeds of up to 50,000 rpm with a choice of fourteen measuring ranges from 0.2 to 5,000 Nm.
Additional benefits are two, switchable ranges, with the second range being either 1:10 or 1:5 of the rated torque, integral digital signal conditioning providing both analogue and digital outputs, contactless signal and power transmission and a speed sensor output of up to 360 pulses per revolution.
The option of two, switchable ranges allows precise measurement of both peak and operating torque with the same sensor. In applications with a high peak but moderate operating torque, a sensor with only one measuring range would have to be selected to withstand the peak torque which would compromise measurement accuracy at the lower operating torque.
The contactless power and signal transmission between the rotating shaft and the stator, combined with precision manufacturing, and high grade shaft balancing, essential for reliable, high speed operation, ensure that the sensors maintain calibration over a long life in both laboratory and production environments. Typical applications include testing of electric motors, generators and drive performance and measurement of transmission or spindle drive friction at manual workstations or networked, automated production cells.
KiTorq Intelligent Torque Measuring Flange
The Kistler KiTorq torque measuring flange system operates without an antenna ring and has standard flange geometry conforming to ISO7646 for easy installation. The open stator design allows faster installation whilst minimising the risk of damage and easier visual inspection during testing. The universal, intelligent stator may be used with any KiTorq rotor of the same speed rating for greater operational flexibility.
A choice of 500, 1,000, 2,000 or 3,000 Nm measuring ranges is available each with an accuracy class of 0.05% of range. The system has an excellent torque signal bandwidth of up to 10 kHz and a 60 pulses per revolution speed output.
A single, intelligent stator can be used with any KiTorq rotor of the same speed rating and will automatically recognise the rotor measuring range. This minimises hardware investment as one stator may be used with rotors of differing ranges for different applications. Installation is simplified by the contactless, digital telemetry that does not require an antenna ring.
For more information, please visit www.kistler.com