Siemens SINUMERIK 828D Operating Manual page 473

Notation for variables
● PLC variables
● NC variables
Note
NC system variables and PLC variables
• System variables can be dependent on the channel. When the channel is switched over,
• For user variables (GUDs) it is not necessary to make a specification according to global
• Using the tooltip, for NC system variables, you can display the OPI notation (with the
Changing PLC variables
Changes can only be made to the PLC variables with the appropriate password.
Changes in the states of NC/PLC variables have a major impact on the machine. Incorrect
configuration of the parameters can endanger human life and cause damage to the
machine.
HMI sl Milling
Operating Manual, 06/2009, 6FC5398-7CP20-0BA0
EB2
A1.2
DB2.DBW2
– NC system variables - notation
$AA_IM[1]
– User variables/GUDs - notation
GUD/MyVariable[1,3]
– OPI - notation
/CHANNEL/PARAMETER/R[u1,2]
the values from the corresponding channel are displayed.
or channel-specific GUDs. The indices of GUD arrays are, just like NC variables in the
system variable syntax, 0-based; this means that the first element starts with the index 0.
exception of GUDs).
DANGER
Alarms, error messages, and system alarms
20.5 PLC and NC variables
473