Siemens S7-400 memory optimize


Thread Starter


Hi All,
I am using Siemens CPU-414 with 8MB RAM memory
card to do program, I use a lot of DB and FB in
my program, but when I checked the PLC memory
information, I found Work momory Code 43% used,
but Load memory RAM 2% used and work memory data
7% used, so far I only completed one third of
my program, I worry about my PLC Work Memory
is not enough. I wonder how I can optimize my
PLC memory and avoid use much Work Memory Code
instead of using other memory thoroughiy.

Thanks and regards
Hi Moli!
try to use SCL package , m.b. is better solution for optimise your code. But if you have expiriense in Pascal.
Best regards Oldfox
From past experience i have found the use of FB's to be only worth while if the code contained in the FB is quite large. A better solution is to use an FC and allocate a DB to the FC rather than using a FB and INSTANCE DB. In this way u can still monitor the code in the FC by monitoring the DB allocated to it - like u can with an instance DB. U do not however have the memory overhead created by the use of Instance DB's.