Setup Dbs For User (Db 68, Db 71) - Siemens SINUMERIK 880 SW 6 Planning Manual

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Setup DBs for User (DB 68, DB 71)

Data blocks DB 66 to 71 are reserved for user data in SINUMERIK System 800. Two of these
data blocks are available on the SINUMERIK 880.
• DB 68 Data words user
• DB 71 Data bits user
The PLC operating system automatically sets up these data blocks in the RAM the first time
the control is switched on. The user data cannot be accessed at the NC screen as standard;
each user data should be supplemented with plain text in order to facilitate operation.
Images for displaying and editing the user data can be generated with the NC workstation.
Users are recommended to utilize user data in cases where the data are to be used by the
PLC and possibly the NC as well. The user data can also be read by NC cycles by means of
CL800 language commands.
The user data are described in the Installation Guide,
Note on application:
By means of user data the machine operator can edit the PLC program and implement branch
techniques depending on the actual machine configuration.
Unlike the PLC machine data, the user data do not enable any Options; they specify actual
states to the PLC program.
Examples:
1. PLC MD specify that the machine has two clamping pressures.
The user data, for example enable the lower clamping pressure.
2. Setting the waiting time of a loader gripper after a clamping operation.
©
Siemens AG 1991 All Rights Reserved
SINUMERIK 880 (PJ)
(64 data words)
(16 data words = 256 bits)
Instructions for the SINUMERIK 880.
6ZB5 410-0HE02
17 Setup DBs for User (DB 68, DB 71)
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