Always the right wire tension
In the production of reinforcing steel, precision, process reliability, and smooth operations are essential. A key element in this process is ensuring that the bending machines are consistently supplied with exactly the right wire tension. Modern contactless angle sensors ensure that this process operates reliably and with minimal maintenance—even under demanding conditions.
Challenge: Consistent wire feed from the coil
In the production of reinforcing steel stirrups, the wire is unwound from large coils and then processed in automatic stirrup bending machines. To ensure that the wire Voltage always Voltage at the correct Voltage , each unwinding station uses a spring-loaded tensioning arm. This arm maintains a constant tension—provided its position is accurately detected.
Unwinding too quickly can cause the wire to knot or jam, while unwinding too slowly leads to interruptions in the production process. The position of the dancer arm is therefore crucial for synchronizing coil unwinding with the bending machine’s material requirements.
Solution: Magnetic angle sensors from Novotechnik
PEDAX GmbH, a leading specialist in machinery for processing reinforcing steel, relies on the magnetic angle sensors of the RFC-4800 series from Novotechnik.
Why this sensor?
The sensor operates on the Hall effect principle—meaning it is contactless, wear-free, and extremely robust. This offers several advantages:
- No mechanical wear
Since the sensor has no moving parts, it is consistently reliable. - Easy installation
The position magnet is mounted directly on the shaft of the dancer arm, while the sensor itself can be mounted at a distance of up to 5 mm. A major advantage: Installation tolerances are not critical. - Industrial-grade design
A housing made of temperature-resistant plastic, encapsulated electronics, and IP67/IP69 protection ratings make the sensor resistant to dirt, moisture, and vibrations. - Flexible interfaces
PEDAX uses an analog voltage signal—but CANopen, J1939, IO-Link, SSI, or SPI are also supported.
In the area of automatic bracket bending machines, the sensors cover a measurement range of 60°. Overall, measurement ranges of up to 360° are possible.
Reliable performance in demanding everyday use
Since 2020, PEDAX has been using RFC-4800 sensors in its production machines—and has received consistently positive feedback from customers ever since. Project engineer Martin Heyen emphasizes how important stable and precise wire feeding is for the entire production process and how crucial reliable angle detection is to process reliability.
Wide range of applications beyond steel processing
Thanks to their ruggedness, high accuracy, and flexible configuration, these sensors are suitable not only for industrial machinery but also for mobile applications. They are resistant to:
- Vibrations up to 2,000 Hz
- Shocks up to 50 g
- Ambient temperatures ranging from –40 to +105 °C
When configured in a redundant setup, they even meet the requirements for safety-related systems in accordance with EN ISO 13849.
The technology behind it: The Hall effect
The sensors detect changes in the magnetic field of a position magnet mounted on a rotating shaft. This enables contactless angle measurement—precise, resistant to aging, and suitable for very compact designs. Thanks to integrated signal processing, even demanding tasks can be implemented in small sensor housings.
