Siemens SIMATIC FM 452, Руководство пользователя

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Settings
9-6
FM 452 Electronic Cam Controller
C79000-G7076-C452-04
9.3 Zero Offset
Definition
With the “zero offset” setting, you shift the zero point in the coordinate system by
the specified value. The sign determines the direction of the shift.
Calculating the New Coordinate
All the values in the shifted coordinate system can be calculated according to the
following formula:
coordinate
new
= coordinate
old
– (ZPO
new
- ZPO
old
)
ZPO
old
is any existing old zero point offset. If no zero offset was active before the
call, set the value 0 for ZPO
old
.
With this formula, you can calculate which coordinate values are adopted, for
example, by the software limit switches.
Sequence of the Setting
1. Enter the value for the zero offset in the channel DB.
– Linear axis:
The zero offset must be selected so that the software limit switch is still
within the permissible range after the setting is read.
– Rotary axis:
The following rule must apply to the zero offset:
amount of zero offset
≤
end of the rotary axis.
2. Set the appropriate trigger bit.
Data Used in the Channel DB
Address Name Type Initial Value Comment
36.6 ZOFF_EN BOOL FALSE 1 = set zero offset
86.0 ZOFF DINT L#0 Zero offset