What is the difference between absolute code and pseudo absolute encoder?

Industrial rotary encoders are divided into absolute value coding and relative quantity coding (also known as incremental coding). Most of us have used incremental encoders. The PLC and servo controller integrate a high speed counter. Calculate the AB phase signal of the encoder. However, most people's understanding of the definition of "absolute value coding" seems vague, why there seems to be a lot of errors in the use of absolute encoders, so there is a "pseudo-absolute encoder" that can swing in the market. Does Rongde Optical introduce the difference between absolute value encoding and pseudo absolute encoder?


Pseudo-absolute encoders: In the market, the definition of absolute value coding is from beginners to familiarity with three levels of cognitive domain, while the first two are areas of understanding absolute value coding, so it has two pseudo-absolute encoders. In fuzzy recognition.


The first layer, the absolute data output is the absolute value encoder - absolute data refers to the determination of the origin coordinates, the multi-bit data output of this coordinate (usually serial output, not pulse count), it only refers to the form of data output. This does not mean that the internal encoding is an absolute value encoding, and there is likely to be internal incremental encoding of the counters and registers.


The second layer, the data is not lost is "absolute value coding"?


There is also a vague and erroneous cognition - "absolute encoders are power saving", so there is a pseudo absolute encoder.


For single-turn absolute encoding (restricting approximately ten-digit encoding), plus multi-turn counter mode, it is still an electronic multi-turn counting process with or without a battery, where the original encoding is only ten digits, but can output more than 27 digits of data. , where the extra data comes from the counter, non-unique encoding - this is not an absolute value encoding.


The third layer is the real absolute coding domain, with no counters. All mechanical in situs have unique pre-existing absolute value codes. How many bits are encoded in the original mechanical position, and how many bits are output, sometimes referred to as a mechanical absolute encoder.


The core meaning of absolute value coding: From a physics point of view, the counting process of non-absolute value coding is related to the time axis. It is a combination of position coding and timeline. This is a multi-physics event. There is always another physical variable. The small probability uncertainty in a certain period of time is only the possibility under what circumstances and under what circumstances. Relative quantity coding is a bivariate coding of angle change + time variable. Absolute value coding is a single big data encoding without a time axis, and the output information is only related to the original encoding of the true angular position. Any code that requires a counter to introduce timeline information inside or outside the encoder is not an absolute value code.


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