10.94 8 PLC Machine Data (PLC MD)
8.1 General
8 PLC Machine Data (PLC MD)

8.1 General

8.1.1 Entering PLC MD (up to SW 2)

You must set the PLC machine data (PLC MD) to adapt the PLC system program to the
machine tool and to the PLC user program.
The PLC MD are transferred from the machine data area to the data blocks on a PLC cold
restart. There they are available to the PLC user program. PLC MD cannot be entered directly
into the data blocks.
The PLC MD that influence the PLC system program do take effect until a cold restart has
been performed. (A cold restart is performed on a change from initial clear mode to normal
mode).
Selecting PLC MD (up to SW 2)
Diagnosis
NC
Diagnosis
NC
start-up 1)
Cycles
MD Initial clear
mode
NC
MD PLC
MD Enter
password Disable
password
User
data User
bits
System
data FB
data System
bits FB
bits
You cannot modify the PLC MD until you have entered a password.
Note
The description of the functions of the bits always refer to the function that is active when the
bit is set. The function that is active when the bit is not set is simply the negation of this
description. MD not described have been set to zero either when the standard MC were
loaded or when the control was started up, or they have been set to a default value indicating
the control configuration.

Note

As from SW 3, start-up of the PLC-MD is performed in the MDD.

For further details, refer to Section MDD.

_______
1) You can prevent selection of "NC start-up" with the key switch, if NC MD 5006 bit 5 = "1".
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SINUMERIK 840C (IA)