Wachendorff WDGA Series, Техническое руководство

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Technical Manual
WDGA with EtherCAT
3 - Description of the equipment
© Wachendorff Automation GmbH & Co. KG 9 Rev.1.09
3.3.1 Single-turn - ST (QuattroMag®)
The measurement of the angle from 0° to 360° using a shaft is an
encoder’s simplest
function. The sensors are based on the optical or magnetic scanning of a material
measure on the encoder shaft.
The WDGA encoders from Wachendorff use the new magnetic QuattroMag®
technology that ensures maximum accuracy and resolution of the single turn.
3.3.2 Multi-turn - MT (EnDra®)
A multi-turn encoder allows the number of revolutions to be recorded. This is carried
out using a revolution counter. To ensure that the relevant information is retained even
when the voltage is switched off, WDGA encoders use EnDra® technology. Buffer
batteries and drives that require a relatively large amount of space and a corresponding
amount of maintenance can therefore be replaced.
3.3.3 Direction of revolution
A simple two-part complement (invert each bit and add "1") of the position value can
reverse the positive direction of revolution.
3.3.4 Preset
In a specific physical position, the encoder can be assigned a desired position value.
This must be within the measuring range so that the position value correlates to a
physical reference position. To do this, the difference between the current position
value and the desired value is calculated. This is stored in a non-volatile memory and
added to the position value as an offset.
3.3.5 Scaling
For the precise matching of the position value with the parameter to be measured in
physical terms, adaptation can be carried out using the scaling parameters. The
scalable parameters are "Measuring units per revolution (MUPR)" and "Total
measuring range in measuring units (TMR)".
The scaling parameters "Measuring units per revolution (MUPR)" - increments per
revolution - specify the resolution of the position value for each revolution (also:
ST -resolution). The value equates to 360°. This means that, if a value of 3600 Cts is
parametrised, the encoder outputs the position in 0.1° increments (see equation (2)).