BEI Sensors PHU9 Absolute Hollow Shaft Encoder - Manual (Page 13)

PROFIBUS USER MANUAL
Preliminary 13
BEI IDEACOD SAS
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4.1.6 Total measuring range
The parameter „total measuring range“ is
used to adapt the measuring range of the
encoder to the real measuring range of the
application. The encoder counts up until the
position value has reached the programmed
total resolution and starts with 0 again.
Example: 100 steps are programmed for each
revolution (parameter „measuring units per
revolution“) and the total resolution is set to 12800. Then the encoder counts up to 11799,
starts with “0” again after 128 revolutions,
counts up to 11799, and so on.
Note: With many software tools it is necessary
to divide the value into high and low word,
refer to page 34.
When choosing the total resolution the
following rule has to be observed:
If “steps per revolution” are set to “n” the parameter total resolution must not cause periods
longer than the maximum (physical) number of revolutions (see type label), i.e. that the
programmed total resolution of a 65536 revolutions multiturn encoder must be less than 32768 x
the programmed number of steps per revolution (the programmed total resolution of a 32768
revolution multiturn encoder must be less than 32768 x the programmed number of steps per
revolution):
The following rules must be applied:
1) Total resolution < 2 147 483 648
2) Total resolution <= measuring units per revolution x 32768 or
Total resolution = measuring units per revolution x 65536
If these rules are disregarded the encoder will indicate a parameter error and it will not enter the
data exchange mode.
Octet 14 15 16 17
Bit 31 – 24 23 – 16 15 - 8 7 - 0
Data 2 31 to 2 24 2 23 to 2 16 2 15 to 2 8 2 7 to 2 0
Programmed total measuring range in steps