S5 can I use 115u 944B in stead of 115u 944?

Hello,
The thing is that I don't have to much experience with siemens and I have a problem, I think the problem is the CPU, because all the red lights are ON ( ST, QV, ZY, BA ) I already tried overall reset several times and tried other way that I read in the forum, Turning off the entire power and remove the batteries, wait 10 minutes and tried to read the eprom.
The program should be in the eprom.
The CPU with the problem is 115u 944, now I can buy 115u 944B but I not sure is could be work. The label from the sides is the same 6ES5 944-7UB21 but in the front one have no B and the other one have B.
Other question, Can I change de CPU and read the program from the eprom or I need to do something else like a do something with computer? Because I don't have any cables and any programs.

I hope you can help me or give me any suggestions.
Thank you!

I know that is a very old version but I have to start the machine and order the update to s7 before.

As far as I remember the 944B model has 2 PG ports. So it should be compatible with the 944 model with only 1 PG port. Is that right, there are 2 ports on the 944B ?

It should be possible to transfer the program via the EPROM. There is the possibility that the program is only stored in battery backed RAM, but since this is a very old control system, it is highly unlikely.

In order to load the program to the new CPU, try the procedure described in this post:
http://www.plctalk.net/qanda/showpost.php?p=8154&postcount=4

And of course, it should be mentioned that you should consider upgrading the old S5 to something newer.
Exchanging old S5 parts only gives you temporary relief.

JesterMP Thank you for your help and advice.

Another doubt is, when I trying to do the overall reset one of the time I forgot to pull the eprom, it is possible that eprom were erase?
Thank you in advance

If it is an EPROM (not an EEPROM) then it can only be erased in a UV-eraser.

Thanks!!!

Hi, everyone
It's possible to use CPU 115 943B instead of 115 944 ?

It's because I found on 115 943B from the other blowmolder for parts.

Normally yes, if the size of the program and data
code isn't too big.

The CPUs are code compatible, if the code is 'advanced' it could be adressing the system areas -that may have different layout. I cannot remember if the 944 has more built-in FBs / OBs.


If I were you, I'd chech the error stacks of the old CPU to try and fint out what's wrong. It could be that the EPROM is defective.

You'll find a good Step5 software by IBH-Softec.
Or you could search for the S5-software 'PG2000'. I'm not sure, but I think you can go online with the trial version.

And you will need an USB/RS232/current-loop converter.

Kalle


Edit: A link to PG2000: https://www.traeger.de/downloads/cat_view/24-softwaretools/25-pg-2000

I tried to install CPU 115 943B in my PLC who have 944 before, but when I tried to load the program from the eprom the stop light just flash and do not stop flashing.

What could be happen?

Thanks in advance

Man, you need to go online and check the diagnostics!

Or we could have a wild guess competition...

Kalle

He dont have any PG.
As I see it, if he can find local expertise in Siemens S5, then it could be possible to try and get it back and running with a spare 944 CPU. To get the old S5 PLC up and running for now is just temporary relief, and the opportunity should be used to start migrating to a newer PLC.

edwinrg69 said:

I tried to install CPU 115 943B in my PLC who have 944 before, but when I tried to load the program from the eprom the stop light just flash and do not stop flashing.

What could be happen?

Thanks in advance

Click to expand...

You can find a manual here:
https://support.industry.siemens.co...5-115u-programmable-controller?dti=0&lc=en-NO

Here's the meaning when the stop led is flashing:

Memory error (block structure damaged)

After CPU COLD RESTART and after POWER UP, a memory error message may result if the user
program contains the TNB, TIR or TDI operations. It is possible to inadvertently overwrite the
following with these operations:
• Block headers
• Memory areas designated as "free" by the operating system.
The operating system writes the erroneous address found when generating the address list
into system data word 103 (EACE
H
). You can display the contents of the system data locations
using the DISP ADDR programmer function.

Special features of CPU 943 and CPU 944:
Error in the use of memory submodules (see Section 5.8)

Special features of CPU 944:
You can detect whether the error in the address list has occurred in memory bank 1 or memory
bank 2 by using the location counters in the two memory banks.
• Location counter for memory bank 1: system data word 33 (EA42
H
)
• Location counter for memory bank 2: system data word 32 (EA40
H
).
Since the location counter is updated only after the address list has been generated, the
location counter of the memory bank with the erroneous address points to its initial value;
1000H in the case of memory bank 1,
1001H in the case of memory bank 2.
If system data word 33 contains the value "1000H
", after a memory error message, the address
in system data word 103 refers to memory bank 1.
The value of the erroneous address can be displayed and interpreted using the DISPL. ADDR.
programmer function. The programmer automatically accesses memory bank 1.


See pages 5-9 + 5-10!
Enjoy!

Kalle