Siemens SINUMERIK 840D sl Function Manual page 47

Default settings via the PLC user program
The keyswitch switch positions are transferred to the NC/PLC interface via the basic PLC
program. The corresponding interface signals can be modified via the PLC user program. In
this context, from the point of view of the NC, only one switch position should ever be active,
i.e,. the corresponding interface signal set to 1. If, from the point of view of the NC, a number
of switch positions are active at the same time, switch position 3, i.e., the keyswitch position
with the least restricted access rights, will be activated internally by the NC.
2.2.5.4 Parameterizable protection levels
Parameterizable protection level
The parameter level can be freely parameterized for a variety of functions and data areas.
The protection level is set via operator-panel machine data, designated as follows:
$MM_USER_CLASS_<
Examples:
$MM_USER_CLASS_READ_TOA
$MM_USER_CLASS_WRITE_TOA
$MM_USER_CLASS_READ_PROGRAM
$MM_USER_CLASS_WRITE_PROGRAM
Default values
On delivery or following standard commissioning, with very few exceptions, the default value
for the protection level will be set to 7, i.e., the lowest protection level.
Basic logic functions: Various NC/PLC interface signals and functions (A2)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Function_DataArea
>
Read tool offsets
Write tool offsets
Read part programs
Write/edit part programs
Detailed description
2.2 Functions
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