S5-115U Hidden programmed Blocks

OK, this is the answer!

As far as I can see, only the following PBs are in the program:

PB1 to PB15, PB30

The S5 reacts differently than the S7 when the program executes a JU/JC to another Program Block that does not exist. The S5 does not go to STOP or present an error, it simply moves on to the next instruction.
 
Hi,
Exactly this is all what I have in PBs....
PB1 to PB15, PB30.
FB0, FB1, FB238...........FB254....

So according to you, PB16 doesn't exist....
Now as this is a DOS based PC interface, What do think, where has the programmer stored the Calculations like Weighing scale monitoring for Actual load and Nominal load comparision, Keyboard function keys commands? I could not find this in given PBs, OPERATOR presses F1 and system shows Automode, Operator presses F6 and Fault is acknowledged, Operator presses F5, and next cycle is blocked.....
is this program stored in DOS? and not in PLC?
 
Well, the PBs that exist are in the EPROM. It is a possibility that the missing PBs being called were in RAM, but they are no longer there.

There are only 2 DBs in RAM: DB10 and DB11, the rest of the blocks (DB/FB/PB/OB) are in EPROM.

The DOS program would only really be reading/writing to DB or F (flag) memory.

Could you post the PLC program itself? You would have to do a Block transfer from PLC to PC. See attached.
 
Dear Sirs,

Please find attached my .S5D file.. Hope we find the missing PBs and the missing logic....

Also, if you could suggest me an Example/Basic program for a Concrete Batching Plant with Siemens S7-300 and Siemens HMI....

Thanks.
Mr. G. M Ansari
 
Sorry, if PB16 to PB69 were in your program, they are gone. Your PLC backup battery might be weak, and should only be changed with power on. There is still a chance that those PB blocks were always missing, but there is no way to tell.

Better check around your plant to see if there is any floppy disk or CD, or ask if anyone did a backup of the PLC. Maybe take a backup image of the DOS hard disk, or at least exit to DOS and go to the C:\ prompt, and do dir *.S5D /s to see if there is a PLC file on the hard disk.
 
Dear SigmaDelta,
As I mentioned earlier, this PC has failed to Start....it is beyond repair..... System Image of this PC, which was with us as Backup, not supporting NEW HARDWARE.....OEM says "OLD PC/BACKUP will not work with New PC and hence purchase a New PC with New program from us".
There is no PLC/PC PROGRAM given by OEM.....

I cannot search anything in the Harddisk.... This PLC was running absolutely fine with all functions enabled before PC failed.....
There was no Battery failure as such..... And if there was any in earlier times, MY MACHINE WAS RUNNING FINE....That means, there existed all the required logic ... And if this was not in PB16....PB69, Where was that?

Hope you understood.....
 
Well, i would try and upload.....Mean while, could you give reference to any Sample Concrete Batching Plant Program for upgradation of this plant to S7?
I searched on Internet and also Siemens Support Site, but i didn't find it.

Thanks.
Mr. G. M Ansari
 

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