HOHNER AUTOMAZIONE SRL

The absolute method give precise position in the form of signals codes, it clearly indicates the direction of increment and the value attained avoiding lengthy calculations. This technique is useful for angular applications; think, for example, of the association that can variable (bit) at once: this technique allows it to precisely interpret the value assumed at the position and it is an extremely convenient code to use in very disturbed environments. The Binary code is used by all calculator equipment: the encoder which supply this code can be useful when it is necessary to save time which may otherwise be spent in converting the code itself. The BCD code is useful in all those systems which require a direct display of the value assumed by the encoder in a certain position (display, counters); this code is split into tenths and each figure represents a tenth. b e obtained between an encoder having 360 position per revolution and the angle of revolution: 1° = 1 position. In areas where electrical failure would make it difficult and costly to correct the encoder, an absolute reading is extremely advantageous: the reading of the absolute The ASCII code (mostly used in serial systems) allows the encoder to communicate directly with a Personal Computer through interface circuit boards and standard or dedicated protocols. We can conclude by advising that incremental encoders be used in applications where positions are required and absolute encoders when a cyclic angular control is needed and/or in the event of a power failure to the encoder. p osition is taken directly from the coded optical disk fixed to the shaft. This allows it to “remember” the position even in the event of a power failure to the encoder.

Signal coding:

Signal codification for absolute industrial encoders: Gray code GRAY Code is that is changes only one BINARY Code BCD 8421 Code Gray, Binary, BCD, ASCII are codes generally used to clearly express the position of the encoder. The main feature of the D4 D3 D2 D1 D0 D4D3D2D1D0 D4D3D2 D1 D0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 2 0 0 0 1 1 0 0 0 1 0 0 0 0 1 0 3 0 0 0 1 0 0 0 0 1 1 0 0 0 1 1 4 0 0 1 1 0 0 0 1 0 0 0 0 1 0 0 5 0 0 1 1 1 0 0 1 0 1 0 0 1 0 1 6 0 0 1 0 1 0 0 1 1 0 0 0 1 1 0 7 0 0 1 0 0 0 0 1 1 1 0 0 1 1 1 8 0 1 1 0 0 0 1 0 0 0 0 1 0 0 0 9 0 1 1 0 1 0 1 0 0 1 0 1 0 0 1 10 0 1 1 1 1 0 1 0 1 0 1 0 0 0 0 11 0 1 1 1 0 0 1 0 1 1 1 0 0 0 1 12 0 1 0 1 0 0 1 1 0 0 1 0 0 1 0 13 0 1 0 1 1 0 1 1 0 1 1 0 0 1 1 14 0 1 0 0 1 0 1 1 1 0 1 0 1 0 0 15 0 1 0 0 0 0 1 1 1 1 1 0 1 0 1 16 1 1 0 0 0 1 0 0 0 0 1 0 1 1 0

Encoder used like simulator of the probe of Hall

Three-phase digital system (S. HALL) For application where the encoder, integrating part of motors to digital control, replaces the Resolver: it is necessary that is in a position to supplying a used beacon three-
Phase H0Phase H1 p hase for the putting in phase of the motor. The encoder it introduces three industrial beacons in quadrature characterised from a phase-
Phase H2 p eriods that generally are comprised between “one” and “eight”, that is between 2 and 16 braces of poles.
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