Absolute encoder & Incremental encoder！

Accordance with the principle can be divided into incremental encoders and absolute categories. Incremental encoder displacement is converted into periodic electrical signals, then converted into electrical signals that count pulse represents the magnitude of displacement by the number of pulses. Absolute encoders at each position corresponding to a certain digital code, so its value is only shown with the beginning and end of the measurement, but not to the middle of the process measurement.

Incremental rotary encoder rotates the output pulse by counting device to know its position when the encoder does not move or power outage, counting on internal memory to remember the location of the device. Thus, when the power failure, the encoder does not have any movement, when work calls, encoder output pulse process, it can not have lost the pulse interference, otherwise, it will count zero offset memory device, and this bias the amount of shift is no way to know, to know only after the wrong production results appear. The solution is to increase the reference point, the encoder after every reference point, the reference position correction position count into the memory device. In the previous reference point, it is not guarantee the accuracy of the location. To this end, every operation in the industrial in there to go first reference point, turn the change and other methods. Such encoder is a mechanical encoder position determined, it is not a power outage, the impact of interference.

Absolute encoder is determined by the mechanical position of the uniqueness of each location, without having to remember it, no need to find a reference point, and would not have to count, when you need to know where and when to go read its position. Thus, interference encoder properties, has greatly enhanced the reliability of the data.

Since the absolute encoder positioning clearly superior to incremental encoder, has been increasingly used in industrial targeting. Absolute encoders because of its high accuracy, the output bit more, if you still use parallel outputs, each of which an output signal of the need to ensure a good connection, but also for more complex conditions isolation, the number of multi-core cable connection, thereby inconvenience and reduced reliability, and therefore, the absolute encoder multi-bit output type, generally use the serial output or bus output, the German production of absolute encoder is the most common serial output SSI (synchronous serial line output).

Multi-turn absolute encoder. Encoder manufacturers use mechanical timepiece gear principle, when the center of the code wheel rotates through another set of code wheel gear (or sets of gear, multiple sets of code disk), single-turn encoder, based on the additional number of turns coding, to expand the measurement range of the encoder, absolute encoder so called multi-turn absolute encoder, it is also determined by the mechanical position encoders, position encoding each unique non-repetition, without memory. Another advantage of the multi-turn encoder is due to the large measurement range, the actual use is often more affluent, so that the installation of unnecessary hard to find zero, as a starting point to an intermediate position on it, and greatly simplifies the installation difficult. Multi-turn absolute encoder positioning advantage in length significantly, it has been increasingly used in industrial targeting.

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