Does the double code magnetic encoder provide relative position information or does each position correspond to a unique code?

The position information type of the double code magnetic encoder depends on its design and application goals, and needs to be analyzed in conjunction with its working principle:

1. Principle of absolute position encoding
The core feature is that each mechanical position corresponds to a unique numerical code value, and the position memory is retained even after power failure. If the double code magnetic encoder adopts a multi turn absolute value structure, it uses a magnetic encoder disc and gear set to encode and solidify the single turn angle and rotation number internally, forming a globally unique position identifier. For example, after the system restarts, the current precise position can be read without returning to zero.

2. Principle of incremental relative position
Relying on pulse counting to achieve position tracking requires establishing a coordinate system based on the initial reference point. A typical double code design generates A/B phase signals with a phase difference of 90 °, and calculates displacement through pulse edge counting and direction discrimination. In this type of design, the encoder only provides feedback on the relative motion, and after power failure, the position information is lost and needs to be reset to zero.

3. Double code redundancy design positioning
Part of the industrial grade double code magnetic encoder combines two modes: the main channel outputs absolute position encoding, and the backup channel provides incremental pulses. When the main channel fails, the system switches to incremental mode and maintains position tracking through an external counter. This design balances absolute positioning reliability with incremental backup flexibility.

4. The decisive impact of application scenarios
Absolute mode is suitable for fields such as wind power variable pitch, mechanical arm joints, etc. that require power-off position maintenance or safety redundancy.
Incremental mode is suitable for scenarios such as servo motor speed control and conveyor belts that move continuously and can be reset periodically.
Hybrid mode is suitable for high reliability demand scenarios such as rail transit and metallurgical equipment, which require double protection.

5. Characteristics support of magnetic encoding technology
Magnetic media are not affected by mechanical wear or contamination, and whether in absolute or incremental mode, double code magnetic encoders can maintain signal stability for a long time. The absolute type uses multi-stage magnetic rings or reluctance arrays to achieve unique encoding throughout the entire stroke, while the incremental type relies on uniformly distributed magnetic poles to generate periodic waveforms.