LD25x
8.4 Basic modes of operation
8.4.1 Normal SSI display
Normal operation provides calculation of the display value from the SSI encoder
data and the settings of the scaling factors. Negative values can be achieved by
corresponding setting of the zero position (
0-Pos
item) or by inversion of the
direction bit (
dir
item).
To set the unit up without problem, it is advisable to use the following sequence
of steps:
•
Set all basic registers according to the encoder type you use, as shown
in section “7.1 Basic settings” on page 14.
•
For better comprehension, use first all initial settings as shown in the list
(xxx = according to need).
M-Factor
:
1.000
Direction
:
0
D-Factor
:
1.000
Error
:
xxx
P-Factor
:
0
Error P
:
xxx
Decimal Point
:
000000
Round-Loop
:
0
Display
:
0
Time
:
xxx
Hi bit
:
see sections 8.2
and 8.3 on page
28 *
Reset
:
no
Lo bit
:
0-Position
:
0
* Please evaluate 19 bits only to avoid overflow.
These settings ensure that the unit displays the pure SSI encoder information at
first.
•
Move your encoder now from a “lower” position towards a “higher”
position according to your own definition of "low" and "high". When
also the display changes from lower to higher values, your own
definition of directions matches with the encoder definition. If not,
change the setting of “Direction” (
dir
item) from “0” to “1” now to
receive the desired sense of direction (changes after further parameter
settings may cause different results) **.
•
Set the desired zero position, either by entering the numeric value to
the “0-Position” register (
0-Pos
item) or by using the Reset function as
described previously. Your zero definition will divide the range into a
positive and a negative zone.
•
At this time you are free to set all other registers according to your
needs.
The subsequent drawings show the principle of evaluation with use of a 13-bit
single-turn encoder, with the direction bit (
dir
item) set to either “0” or to “1”
and with the zero position register (
0-Pos
item) set to “1024” **.
**
Subject of correct sequence with parameter settings.
MAN LD25x E 1.0.odt
Hints for application
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