The main purpose of the encoder which some are there?

Rotary encoder is a rotating displacement is converted into a string of rotary sensor of digital pulse signal, the pulse can be used to control the angular displacement, if encoder with the gears or helical screw together, can also be used to measure the linear displacement. Encoder generated signals is controlled by a number of place after CNC, PLC programmable logic controller, control system, etc. To deal with. The sensor is mainly used in the following aspects: machine tools, materials processing, motor feedback system and measurement and control equipment. In ELTRA encoder angular displacement of the conversion principle of photoelectric scanning is adopted. The rotation of the reading system is based on the radial index plate, the indexing is composed of alternating transparent window and opaque window. All the system using an infrared light source vertical irradiation, so light is put the plates on the image projected onto a receiver on the surface, the receiver is covered with a layer of grating, known as the collimator, it has the same window and cd-rom. Receiver's job is to feel the disc rotation generated by the light changes, then the light is converted into the corresponding electric changes. Generally, rotary encoder also can get a speed signal, this signal feedback to frequency converter, adjusting the frequency converter's output data. Fault phenomena: 1, the rotary encoder (bad No output) , the inverter can't work normally, becomes slow, and in a short while inverter protection, display 'PG disconnect. 。 。 Joint action to play a role. Rises to a higher level to make electrical signals, and produces no interference of square wave pulse, it must use electronic circuit to deal with. Encoder pg wiring connection between pg and parameter vector inverter and encoder, must correspond to encoder pg models. Pg type differential output, in general, the encoder open collector output and push-pull output three kinds, the signal transmission way must consider the frequency converter of pg card interface, so choose the appropriate pg card type or set is reasonable. Generally divided into incremental encoder and absolute, they are with the biggest difference: in the case of incremental encoder, starting from zero position mark the number of pulses, and the position of the absolute encoder is set by output code reading. In a circle, the output of each position code reading is the only; Therefore, when the power is disconnected, the absolute encoder is not separated from the actual position. If power on again, then position reading is still current, effective; Don't like incremental encoder, it is necessary to look for zero mark.