The output forms of rotary encoder

An NPN/PNP Open Collector output (NPN/PNP Open Collector) :

NPN open collector output

The most basic way of output, anti-interference ability is poor, the output range is short. For incremental encoder output in the rotary encoder, use fewer now.

Transmission medium: all wires, optical fiber, radio

Good high frequency characteristics:

The picture on the right of NPN open collector output.

Second line drive (TTL/RS422)

Line drive

Symmetry of positive and negative signal output, strong anti-interference ability, maximum transmission distance is 1000 m.

Transmission medium: twisted pair

Good high frequency characteristics:

In rotary encoder and the industrial control system has been widely used as electrical connection in the interface.

Three push-pull output (Push - Pull) :

Combination of two output NPN and PNP, symmetrical positive and negative signal output, can be easily single-ended receiving barge, strong anti-jamming capability, (difference) receiver; The maximum transmission distance of 100 m.

Transmission medium: twisted-pair (difference) receiver; All wires, optical fiber, radio (single-ended receiving).

With the characteristic of high frequency:

Four other:

Other way of interface and RS232 (C), RS485 and commonly used SSI absolute encoder, a variety of field general line (such as Profibus, Devicenet, CANopen, etc.).