Lika DRAW WIRE SFA-10000 Series, Руководство пользователя, Страница: 54 / 72

SFA-5000 • SFA-10000 Profibus
EXAMPLE
We install the following draw-wire encoder: SFA-
5000
-
PB
-
8192
-PG.
The physical values are:
Stroke per turn of the drum = 200 mm (7.874”)
Physical resolution per turn = 13 bits = 8,192 cpr
Max. number of physical revolutions = 4,096
Total physical resolution = 25 bits = 33,554,432 information
Physical linear resolution = 0.024 mm = 24 µm
Max. number of turns of the drum = 25
Max. measuring length = 5,000 mm (196.85”)
Number of information = 204,800
Let's suppose that we need a tenth of a millimetre linear resolution in the
specific installation.
•
Enable the scaling function (
Scaling function control
= 1); byte 10 =
0A hex (bit 1 = bit 3 = “1”)
•
Custom resolution per turn =
Counts per revolution
= 2,000 cpr; bytes
11 … 14 = 0000 07D0 hex
•
Linear resolution = 0.1 mm = 100 µm
Linear resolution =
Stroke per turn
=
200 mm
= 0.1 mm
Counts per revolution
2,000
The custom number of revolutions can be as the physical number of revolutions:
Custom number of encoder revolutions =
Total resolution
= 4,096
Counts per revolution
•
Total resolution
= 8,192,000; bytes 15 … 18 = 007D 0000 hex
NOTE
Please note that if you set a preset along the path, when the encoder moves
back and cross the zero, the value immediately after 0 will be 8,192,000 - 1, i.e.
8,191,999.
... 8,191,997 8,191,998 8,191,999 0 1 2 ...
MAN SFA_5000_10000_PB E 1.0 Profibus® interface 54 of 72