Wachendorff WDGA Series, Техническое руководство

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Technical Manual
WDGA with EtherCAT
3 - Description of the equipment
© Wachendorff Automation GmbH & Co. KG 10 Rev.1.09
𝑀𝑈𝑃𝑅 = 𝑆𝑇 = 3600 𝐶𝑡𝑠
(1)
𝑎𝑛𝑔𝑢𝑙𝑎𝑟 𝑠𝑡𝑒𝑝𝑠 =
𝑎𝑛𝑔𝑙𝑒 𝑜𝑓 𝑜𝑛𝑒 𝑟𝑒𝑣𝑜𝑙𝑢𝑡𝑖𝑜𝑛
𝑀𝑈𝑃𝑅
=
360°
3600 𝐶𝑡𝑠
= 0,1°/𝐶𝑡𝑠
(2)
The scaling parameter "Total measuring range in measuring units (TMR)" - maximum
overall measuring range of the position value (single-turn and multi-turn multiplied) -
indicates the encoder's overall resolution. Once the position value reaches TMR - 1, it
skips back to 0 and vice versa.
Generally speaking, the TMR parameter is chosen so that it is a whole integer multiple
of the "Measuring units per revolution (MUPR)" (see equation (4)), so that the zero
point is always located at the same position on the encoder shaft.
𝑇𝑀𝑅 = 36000 𝐶𝑡𝑠 (3)
𝑀𝑇 =
𝑇𝑀𝑅
𝑀𝑈𝑃𝑅
=
36000 𝐶𝑡𝑠
3600 𝐶𝑡𝑠
= 10 (4)
In exceptional cases, the TMR does not need to be a whole integer multiple of the
MUPR. For example if a translation in a system causes the desired measuring
parameter to move 10% faster in relation to the encoder shaft than the encoder shaft
itself.
In this case, the setting of MUPR = 3960 Cts and TMR = 36000 Cts would ensure that
the faster, but not directly measurable, shaft can be measured with a resolution of 0.1°
and over a range of 10 revolutions. Normally, it would be possible to calculate the
revolution speed by dividing the position value by the MUPR. In this case, however, it
must be divided by 3600 Cts since the result would otherwise be the revolution speed
of the encoder shaft and not the speed of the faster shaft in the system.

It should be noted that measuring errors occur if the result of
this formula is a decimal.