Incremental Encoders: Still the Workhorse of Industrial Automation
Incremental encoders are not a new technology, but they are still widely used in industrial automation. The reason is simple: in many machines, the system does not always need absolute position. What matters more is speed, movement change, response time, and stable feedback.
Wherever speed control, counting, displacement change, or motion rhythm is required, incremental encoders are often a practical and reliable choice.
I. How Incremental Encoders Work
An incremental encoder does not store the current position. Instead, it outputs continuous pulse signals as the shaft rotates.
The more the shaft rotates, the more pulses are generated. The faster the shaft rotates, the denser the pulse frequency becomes. The controller counts these pulses and calculates speed, displacement, and direction.
For a typical ABZ incremental encoder, A and B phases are used for direction and counting, while the Z phase provides a reference pulse once per revolution.
Because it records movement change rather than absolute position, an incremental encoder usually requires homing after power loss. From an engineering perspective, this is a practical trade-off for simpler structure, fast response, and easy integration.
II. Why Incremental Encoders Are Still Popular
Incremental encoders remain popular because they are simple, stable, and easy to use in real industrial systems.
Common advantages include:
2.1 Non-contact sensing structure, reducing mechanical wear.
2.2 Standard ABZ square-wave signal, highly compatible with PLCs, counters, servo drives, and motion controllers.
2.3 Fast response, suitable for real-time motion feedback.
2.4 Simple system structure, easier commissioning and maintenance.
These advantages make incremental encoders suitable for automation lines, motor speed feedback, conveyors, robotic arms, AGVs, packaging machines, textile equipment, and general motion control systems.
III. Optical or Magnetic: Choose by Environment
Optical incremental encoders usually offer high resolution and high accuracy. They are suitable for standard industrial environments where precision is important.
Magnetic incremental encoders are more suitable for harsh environments. They perform better in applications with vibration, dust, oil, moisture, or contamination.
Although the sensing principles are different, the signal logic is similar. Both types can provide ABZ pulse signals for speed, direction, and position change feedback.
IV. Key Points for Encoder Selection
In many applications, encoder problems are not caused by the encoder itself, but by incorrect selection or installation.Before selecting an incremental encoder, several points should be checked.
Output Type Matching
The encoder output must match the controller input. Common output types include NPN, PNP, Push-Pull, TTL, HTL, and Line Driver.
Resolution Matching
Resolution should match both the required accuracy and the actual shaft speed. Higher resolution is not always better. If the pulse frequency exceeds the controller’s capability, missed pulses may occur.
Noise Immunity
For long-distance transmission or environments with motors, inverters, and electromagnetic interference, differential output and shielded cables are often recommended.
Mechanical Installation
Shaft alignment, coupling selection, mounting stability, and vibration all affect encoder performance. A reliable installation is just as important as the encoder itself.
V. Incremental Encoders Are Not “Low-End”
Incremental encoders are not outdated. They remain widely used because they offer a practical balance between response speed, stability, system complexity, and cost.
For applications focused on speed, counting, displacement change, or motion process control, a properly selected incremental encoder can be more suitable than a more complex solution.
BriterEncoder provides incremental encoder solutions for real industrial applications, focusing on signal stability, environmental adaptability, mechanical reliability, and easy system integration.
Need help selecting the right incremental encoder? Contact BriterEncoder for one-on-one technical support and model selection guidance.
