1, encoder shaft rotation change, encoder installation, the corresponding rotary shaft zero, the general increment and lap absolute value will use this method, while the sleeve-type encoder also use this method. Shortcomings, zero is not easy to find, low accuracy.
2, with the above method is equivalent, but the encoder shell rotation change, which is mainly for some compact installation of synchronous flange (also called servo flange) shell used,
3, the power to move the installation of mechanical zero, power will move the installation of machinery to the corresponding encoder zero position corresponding installation.
4, Offset calculation, machinery and encoder do not need to change, according to the deviation of the encoder readings and the actual position of the calculation, get the offset, after the encoder reading minus the offset. For example, if the encoder reading is 100 and the actual position is 90, the encoder reading should be 10 when calculating the actual position 0, and the “10” is the offset. Afterwards, the encoder reads the number minus Go to this offset is the position value. It can be repeated several times to correct the offset. For incremental encoders, the reading from the original mechanical zero to the first Z is taken as the offset. More accurate encoder, or larger absolute value multi-turn encoder, use this method.
5, intelligent external zero, some with intelligent features of the encoder, can provide external set function, such as with the encoder with the key, or take the software set to zero.
6, It should be noted that the zero point of the absolute encoder is the maximum value of the encoded loop, no matter the absolute value of the single loop or the absolute value of the multiple loops. If the zero bit is set, then move downwards , Inertia overshoot, etc.), it is possible that the data will jump to the maximum at a moment’s notice. For the absolute value of the high order multiple times, the data may overflow the original setting range. In addition, the absolute value of the encoder there is a problem of rotation direction, set to zero, if the wrong direction, jump from 0 to maximum, and then from big to small. Some imported encoders with external zero function, but it is recommended or not to use this feature. (We encountered a lot of imported absolute encoder will encounter such confusion, do not import on superstition).
7, the best method of setting, presetting a non-zero bit (leaving slip, overshoot margin) and preset rotation direction + offset calculation method. Another way is to set “in”, the offset is the midpoint value, set the line and the power is in direct contact with the encoder output is the midpoint position, this trip is +/- half full, in this Travel range, regardless of direction of rotation, to ensure that will not go through the zero jump.

Leave a Reply