High-precision torque measurement flanges for all industries
ATESTEO torque meters measure the torque occurring in the drivetrain and provide measurement data for specimen analysis and test bench control. Whether you require high-precision efficiency measurements or multifunctional endurance testing, ATESTEO offers the right measurement technology for measuring the torque for your system or test sample. Multi-channel torque sensors enable high test bench utilization by reducing the need for modifications.
The torque transducers operate contactless between the rotor and stator and are designed without bearings. This means they measure without friction losses and are maintenance-free. Many series can be equipped with a speed sensor. The use of three different measurement methods (inductive, optical, magnetic) enables robust speed measurement for a wide variety of test requirements. Torque meters for special requirements such as torque and temperature measurement, as well as flanges with a central bore, are already available as sophisticated systems. Customer-specific requirements for the flange design or sensor electronics can be implemented upon request by our engineers.
State-of-the-art calibration facilities in the accredited ATESTEO calibration laboratory
Every ATESTEO torque transducer is calibrated in our own accredited calibration laboratory on state-of-the-art calibration equipment. The characteristic values (sensitivities) are determined on the professional equipment. Highly accurate and traceable measurement results are thus ensured. The DAkkS-accredited calibration laboratory also offers this service for third-party products. Optional calibrations according to DIN 51309 are available.
Customised measurement shafts and torque measuring flanges
Besides standard torque measuring flanges, ATESTEO offers application-specific customer solutions from 1 Nm to 500 kNm. The sensor telemetry used is variable and can be adapted to specific requirements. Examples of customer solutions may include:
- Multi-channel capability such as torque and temperature
- Customized measuring ranges
- Different geometrical designs for stators and rotors
- Stationary measuring shafts – passive and active
- Measuring shafts made of titanium
- Rotors with central bore to accommodate a shaft
FAQ – Frequently asked questions about torque meters
The measurement uncertainty of torque meters and torque transducers is determined from the accuracy values of the sensor and from the ambient conditions. The environmental conditions are, for example, temperatures or the influence of parasitic loads (lateral forces, bending moments). The parasitic loads must be measured, calculated, or estimated, depending on the requirement for the accuracy of the measurement uncertainty. The input data are ultimately converted into a measurement uncertainty value through a physical formula. ATESTEO is happy to assist with the calculation of the measurement uncertainty.
The DF series torque meters offer a third measuring channel. This third measuring channel is called the overload channel. It can be used to measure torque values of up to 300% relative to the nominal torque (Mdn) of the sensor. Although the DF series torque sensors switches to an error mode when the valid measuring range (110% of Mdn) is exceeded, the torque can still be measured via the overload channel. This is particular helpful in analyzing undesired sequences (error in the automation sequence, problem in the test specimen/set-up, etc.).
Most of our ATESTEO torque meters can be manufactured with customized nominal (rated) torque ranges. Because accuracy is relative to the nominal torque, this can improve accuracy in the system. However, it is possible that items with customized nominal torque ranges may result in increased costs or longer delivery times. Please contact us. We would be delighted to assist you.
We not only offer standard torque meters, but on request, we will develop special solutions with our customers. Adapted nominal (rated) torque ranges are usually not a problem. In addition, we can build torque meters (torque measuring shafts) that have a design customized to the equipment of the customer. Our design engineers discuss the customer requirements in detail and create proposed solutions. After the customer has approved the design, the components are produced in our own in-house mechanical workshop. We are also able to deliver customized solutions of the software and electronics. Please contact us; we would be pleased to assist you.
ATESTEO offers a second measuring range in many of its torque meters. A separate amplifier section in the rotating measuring body allows smaller torque values to be measured more accurately than with the main amplifier section. This gives the torque measuring shaft a second physical measuring range (second nominal [rated] torque). The ratio between large and small measuring range (spread) is up to 1:5. So-called dual-range measuring flanges (dual-range torque meters) offer the advantage of being able to measure test cycles with small and large torques. This can eliminate the need to exchange the torque measurement equipment. Only the switchover of the measuring range, a relief run, and a zero adjustment in the load-free state are necessary.
A torque meter receives two sensitivity values after it has been calibrated. The sensitivity value is used to convert the raw measured value into a torque measured value. Therefore, the sensitivity value has the unit “Hz/Nm” or “digits/Nm”. One of the two sensitivitiy values converts the measured value of a positive loading direction (clockwise) into a torque value; the other sensitivity value converts the measured value of a negative loading direction (counterclockwise) into a torque value. To achieve maximum accuracy, both sensitivity values must be stored in the data recording system (measuring system or control system). If the data recording system only allows the input of one value, an averaged slope value can be calculated (with slight decreases in accuracy).
Various parameters of a torque measurement shaft have an influence on the accuracy of the measurement signal. These parameters are:
- Non-linearity, including hysteresis
- Relative standard deviation of repeatability
- Temperature influences on the zero point and the output signal
The accuracy class is determined by the worst of the named parameters. For example, if a torque transducer has the following accuracy values:
- Non-linearity, including hysteresis <= ±0.03%,
- Relative standard deviation of repeatability <= ±0.03%, and
- Temperature influences on the zero point and the output signal <= ±0.05%,
this results in an accuracy class of <=±0.05%.
The accuracy class always refers to the best output type of the sensor. For torque measuring shafts, this is usually the frequency output.
The percentage specification of the accuracy value refers to the nominal (rated) torque of the torque sensor. The accuracy class is not to be confused with the measurement error or uncertainty. The resulting measurement error is composed of the four parameters mentioned above and can be increased by parasitic loads (e.g., bending moment in the lateral direction) and environmental conditions. For an accurate error assessment, a measurement uncertainty analysis must be performed. ATESTEO is happy to provide support with this.
Bei der F-Serie und Systemen, die auf der F-Serie basieren, gibt es meist zwei Varianten. Die Variante “iS” besitzt unterhalb des Ringstators ein Gehäuse, in dem die Auswerteeinheit (Elektronik) verbaut wird. Bei der “eS”-Variante ist die Auswerteeinheit vom Ringstator abgetrennt und in einem separaten Gehäuse installiert. Die eS-Variante erlaubt an der drehenden Welle etwas höhere Temperaturen und hat einen kleineren Platzbedarf im Wellenbereich. Die iS-Variante benötigt keinen zusätzlichen Halter für die Auswerteeinheit und ist preisgünstiger.
For planning a facility, ATESTEO provides design data on its torque meters. The data are dimensional drawings or 3D models (e.g., STEP files). Many torque sensors can be found around the clock on Traceparts.com. Dimensional drawings and 3D models can be downloaded from there. In any case, you can also request data directly from us. Just send us a request via email (equipment@atesteo.com).
Jede ATESTEO-Drehmomentmesswelle kann diverse Stati, wie Fehler oder Alarme, verschicken. Dies geschieht zum Beispiel über Digitalausgänge oder ein detailliertes Statuswort auf dem CAN-Bus. Mit diesen Signalen kann die Anlage den Zustand der Drehmomentmesswelle automatisiert überwachen (Monitoring). Bei Fehlern oder Problemen können tiefergehende Analysen über die Konfigurations-Software (siehe “Wie kann ich eine Drehmomentmesswelle konfigurieren?”) durchgeführt werden. Hierbei hilft unser Service-Team gerne.
Im Produkt enthalten ist typischerweise eine Werkskalibrierung (siehe Text im Angebot). Als Ergebnis aus der Werkskalibrierung wird ein Testreport erstellt, in dem die Steigungen der Drehmomentmesswelle notiert sind. Damit kann die Drehmomentmesswelle betrieben werden. Optional kann ein Werkskalibrierschein miterworben werden. Er liefert weitere Details zum Kalibrierverlauf und den Messwellen-Charakteristiken. Weiterhin können in Abhängigkeit vom Nennmoment andere Kalibrierverfahren optional angewendet werden. Dazu zählt zum Beispiel eine Kalibrierung nach DIN 51309.
Die Kalibrierung wird auf das Hauptsignal, den Frequenzausgang, angewendet. Weitere Ausgangstypen können auf Anfrage kalibriert werden.
ATESTEO-Drehmomentmesstechnik wird im hauseigenen Kalibrierlabor kalibriert.
ATESTEO torque meters are already preconfigured on delivery and can be immediately used. Adjustment of the settings by the customer is only necessary if functions deviating from the standard are required (e.g., CAN bus). For adjusting settings, there is a configuration interface for each torque meter. For the F series and series of F technology, a Windows software program (TCU-Config) is connected to the sensor via RS232. This makes configuration easy. The DF series of torque transducers provides a configuration web page. It can be easily accessed via Ethernet and a browser. Settings can be made using the intuitive web interface.
In a torque measuring shaft (torque meter), torque causes the measuring body to twist; this twisting is initially measured with the aid of strain gauges. The strain gauges theoretically provide an infinite number of measured values per second. This raw signal is converted into a digital signal (frequency, data word) by electronic components. The conversion is achieved by internal high-frequency sampling. The outgoing measurement signal is now discrete in time and provides a limited number of measured values per second. The dynamics of a torque meter define the maximum frequency that can be measured with the measuring signal via signal analysis.
Torque meters are usually calibrated without a measuring system/data recording. This is why testing the measuring chain after receiving the torque sensor is a good idea. Torque meters from ATESTEO offer the function of a test signal for this purpose. This signal can be activated via the configuration software. When the test signal is active, the sensor does not output a measurement value, but rather, a precisely defined signal. The definition of the signal can be found in the test report. The end of the measuring chain should be compared to this reference value.
