Siemens SIMATIC HMI 177 - Page 37

Mounting and Connection
4.2 Connecting the terminal box
Mobile Panel 177 (WinCC flexible)
Operating Instructions (Compact), Edition 07/2005
4-15
Communication Switch setting
5656

21
%XWWRQ 21

21
Compressing the internal program memory with SIMATIC S5
Caution
Compressing the internal program memory
Compressing the internal program memory of the SIMATIC S5 PLC ("Compress" PU
function, integrated FB COMPR) is not permitted if an HMI device is connected! When
memory is compressed, the absolute addresses of the blocks in the program memory
change. Since the HMI device only reads the address list during startup, it does not
recognize the address change and accesses the wrong memory areas.
If you cannot avoid compressing memory during operation, turn off the HMI device before
running the compress function.
Connecting a PLC to a Terminal Box PN
The following figure shows the connection of the PLC to the Terminal Box PN.
352),1(7
6WDQGDUG6YLD7&3,3 6WDQGDUG6YLD7&3,3
352),1(7
6,0$7,&6