Ring force sensor ±100N to ±20 kN for tension and compression measurements

Overview

The KR71 is a ring force sensor designed for precise measurement of tension and compression forces in test benches and machines within industrial environments, R&D testing, or test laboratories. Its flat design (height 23 mm or 27 mm depending on version) allows integration into confined spaces while ensuring uniform force application via its central opening. This sensor is particularly suited for test benches, assembly lines, and quality control applications where compactness, precision, and reliability are essential.

Key specifications

The KR71 is available in 8 distinct measurement ranges (±100 N, ±200 N, ±500 N, ±1 kN, ±2kN, ±5kN, ±10kN, ±20kN) with an accuracy class of 0.1% of full scale. Its robust mechanical design ensures resistance to repeated load cycles, even in demanding industrial conditions. Mounting is performed directly from the tool side, simplifying integration into force transmission systems without requiring complex fixings.

Mechanical integration

The sensor is mounted via its central opening, enabling uniform force transmission. Its compact dimensions (diameter 71 mm) facilitate insertion into existing setups with limited space. Optional versions include protections suited for harsh environments (IP68, extended temperature range, vacuum or pressure compatibility).

Dimensions

Version ±100N to ±2 kN	Version ±5kN to ±20kN

Data acquisition

The KR71 delivers a strain gauge bridge signal (mV/V) via an M12 connector. This signal is compatible with all conditioners in the GSV range, including the GSV-3USB, which ensures signal conversion, bridge power supply, and transmission to a PC via USB. The signal can also be connected to a conditioner with analog output (0–10 V, 4–20 mA) for interfacing with a PLC or industrial controller, or to a process display for local visualization.

Display	Display	Analog conditioner	Analog conditioner	Analog conditioner	Acquisition module
GSV-2TSDI	MICRA-M	PMI-520AJ	GSV-1A	GSV-6K	GSV-3USB
24-bit display with acquisition function	Simple display	Precision analog conditioner with voltage or current output	IP66 analog conditioner with ±10V or 4-20mA or 12±8mA output	In-line conditioner with ±10V or 4-20mA or 12±8mA output	USB acquisition module

Calibration

Each KR71 sensor is delivered by default with a factory sensitivity report. For applications requiring formal metrological traceability, documented factory calibration or ISO 17025-accredited calibration (COFRAC equivalent) is available as an option upon request. These services meet the requirements of quality systems (ISO 9001, IATF, etc.) and periodic verification procedures.

Applications

The KR71 sensor is designed for applications requiring precise and reproducible force measurements in confined spaces. Its performance makes it a preferred choice for automation, precision mechanics, and quality control sectors.

• Industrial test benches
• Automated assembly lines
• Quality control and material testing
• Production process automation
• Precision mechanics applications

Dimensions

Version ±100N to ±2 kN	Version ±5kN to ±20kN

Connectivity

Cable 24-4 PUR 4 wires - length 3 m

• IP68 protection (from 200 N nominal force)
• Extended temperature range: -40°C to 180°C
• Vacuum-compatible version (from 10 mbar)
• Pressure-compatible version (up to 8 bar)

The KR71 delivers a strain gauge bridge signal (mV/V) via an M12 connector. This signal is compatible with all conditioners in the GSV range, including the GSV-3USB, which ensures signal conversion, bridge power supply, and transmission to a PC via USB. The signal can also be connected to a conditioner with analog output (0–10 V, 4–20 mA) for interfacing with a PLC or industrial controller, or to a process display for local visualization.

A few examples:

• GSV-2TSDI: 24-bit display with acquisition function
• MICRA-M: Simple display
• PMI-520AJ: Precision analog conditioner with voltage or current output
• GSV-1A: IP66 analog conditioner with ±10V or 4-20mA or 12±8mA output
• GSV-6K: In-line conditioner with ±10V or 4-20mA or 12±8mA output
• GSV-3USB: USB acquisition module