The encoder is a three terminal resistance, according to a certain change law regulating resistance element.
The encoder usually consists of resistance and removable brush.
As it moves, a brush along the resistance on the output side won the relations with the displacement with a certain resistance or voltage.
Encoder can be use as three-terminal device also can be used for two-terminal element.
The latter can be regarded as a variable resistor.
Encoder, then, what are the main features?
The parameters of the encoder and characteristics.
Encoder is the main characteristic of output function characteristics, conformity, resolution and sliding noise, the nominal value, allowable deviation, rated power of the encoder and the parameters such as temperature coefficient of resistance with a resistor.
Index of the encoder and wear life and starting torque, etc.
Encoder output function features.
The encoder voltage ratio (
The ratio of the output voltage and input voltage)
And stroke than (
Brush resistance in to the Lord by the ratio of the stroke and total stroke)
The function relationship between, also called value change rule.
There are three kinds of commonly used functions relations: linear, exponential and logarithmic type.
And is suitable for the special purpose of sine and cosine forms, etc.
The encoder conformity.
The real output of the encoder function characteristics and the degree of deviation between the theoretical value, with the theory of the actual output and lose the absolute difference between the values expressed as a percentage of.
For linear encoder, compliance with linearity, said the scope of its allowed deviation is called linear precision.
The encoder resolution.
Encoder on the output voltage or resistance of the fine adjustment ability, characterization of brush minimum motion can cause changes in output.
It is important for precision instrument or the control system of regulating effects.
The encoder sliding noise.
Brush on the resistor body movement caused by the irregular parasitic potential (
Assuming that there is no thermal noise and current noise)
, not the sliding line around the encoder with dynamic noise or smooth;
Wire-wound encoder sliding noise in equivalent noise resistance.
Above summarizes the five main characteristics of the encoder, hope to understand the encoder will help.