Cable Extension Transducers: A versatile tool for position measurement

In applications such as automation equipment, medical beds and treatment arms, mobile and agricultural equipment, hydraulic cylinders and structural testing, accurate measurement is critical to ensure precise operations. One of the components that delivers this is the cable extension transducer, also known as a string potentiometer or draw-wire sensor.

What is a cable extension transducer?

A cable extension transducer converts the linear movement of an object into an electrical signal that can be interpreted and analysed. The device consists of a flexible steel cable wound around a spool inside the transducer housing. As the object moves position, the cable extends or retracts, rotating the spool. The spool’s rotation is then translated into an electrical output, which can be measured to determine the position of the moving object.

Applications of cable extension transducers

Cable extension transducers are widely used across multiple industries due to their adaptability and range. Common applications include:

1. Industrial Automation: In manufacturing environments, these transducers are essential for measuring the movement of machine parts, tracking material length or ensuring accurate displacement in assembly lines.
2. Heavy Equipment: In construction and agricultural machinery, cable extension transducers help monitor the movement of booms, cranes and hydraulic components. By ensuring precise measurement of lifting or extending parts, they contribute to safety and operational efficiency.
3. Medical Devices: From tracking patient bed positions to controlling treatment arms, cable extension transducers are integral to many medical devices where precise linear motion is needed.
4. Aerospace & defence: In aerospace, they are utilised in testing equipment for aircraft, helping in simulation and stress-testing components like landing gear or flaps.

Advantages of cable extension transducers

1. Wide range of measurement: Cable extension transducers are capable of measuring both short and long distances, often ranging from a few millimetres to several metres. This makes them highly versatile compared to other position sensors.
2. Compact design: Despite their ability to measure long distances, cable extension transducers are typically compact. Their spool-and-cable design allows them to fit into applications where space is limited.
3. Durability: Built with rugged materials and protective housings, these sensors are designed to withstand tough industrial environments, including exposure to dust, moisture and physical wear.
4. Ease of Installation: Installation of cable extension transducers is typically straightforward. Because the cable can extend and retract, the sensor does not need to be mounted in line with the moving part, providing more flexibility in setup.

Cable extension transducers are a reliable, versatile and cost-effective solution for position and displacement measurement in a wide range of applications. Their ability to measure over long distances, withstand tough environments and provide consistent feedback makes them an excellent choice for both industrial and specialised applications. Our sister company, CPI, has recently introduced the CTU Series Cable Extension Transducer, which we are pleased to offer as part of our linear position sensor range. With 4 stroke lengths ranging from 120mm-1270mm, a reinforced Nylon 66 enclosure, a durable ETFE-coated stainless steel cable, versatile mounting options and a free release mitigated design, it is a great option for OEMs in search of efficiency and precision

For more details about cable extension transducers and how they can benefit your specific application, please visit our website or contact our technical team at [email protected]