Wire Draw Encoder | cable Pull Sensor - Ready Stock Complete units / Spares/ Services

A wire draw encoder (also known as a draw-wire sensor, string encoder, or cable extension transducer) is a electro-mechanical device used to measure linear position, distance, and speed. It works by translating linear movement into rotary movement via a flexible, spring-loaded cable wrapped around a drum

1. The Core Mechanism: A stainless-steel or specialized high-performance composite (like Dyneema) wire is wound around a internal precision bobbin/drum
2. Spring Tension: An internal spring mechanism maintains constant, uniform tension on the wire so that it automatically retracts cleanly when relaxed.
3. Rotary to Linear Translation: The drum is directly coupled to a high-precision rotary encoder. As the wire extends or retracts, the drum spins.
4. Signal Generation: The encoder translates these physical rotations into proportional electrical pulses or digital values, calculating the precise distance traveled.

• The Wire / Cable: Typically made of braided stainless steel or ultra-high-molecular-weight polyethylene.
• The Mechanical Box: Houses the spring-loaded reel and protects the assembly from dust and moisture.
• The Rotary Sensor: This can be an Incremental Encoder (outputs pulses to track change in position) or an Absolute Encoder (outputs unique, discrete data positions even after a power loss).

• Long Measuring Distance: They can measure ranges from just a few inches up to over 40 meters (130+ feet). 
• Flexible Alignment: The cable can be redirected around obstructions using deflection rollers, meaning it doesn't require a strict, perfectly straight path.
• High Durability: The delicate electronic components (the encoder) stay sealed in a heavy-duty housing, while only the rugged wire is exposed to the movement zone.
• Space-Saving Design: The sensor body sits in a fixed location, and only a tiny eyelet needs to be attached to the moving part.

• Heavy Machinery: Telescoping crane booms, forklifts, and scissor lifts.
• Factory Automation: Conveyor systems, injection molding machines, and wood/stone-working machinery.
• Medical Equipment: Patient positioning on automated tables or scanning beds.
• Hydroelectric Facilities: Tracking the opening percentage of large sluice gates and water valves. 

• SICK: Known for modular, tool-free plug-and-play integrations.
• Dynapar: Offers rugged designs specialized for manufacturing lines and heavy industrial environments.
• Kübler Group: Specializes in load monitoring and high-linearity variants for mobile cranes.
• SIKO Global: Excellent for compact form-factors with non-contact magnetic sensing.