modicon 2.5

I am having a problem downloading a new program. I do not
have the original program but i can download the new change
with no problem. When i lose power to the processor i lose the
new change and the original program comes back. Can anybody
tell me what i am doing wrong? I have a modican plc 2.5 version.

You need to be more specific as to the software package you are using as well as the specific processor. If you do not have the original program how are you making changes? Does your processor have a working battery?

I will getthe info on the software and the processor. What i did to
make the change was a upload then made the change and downloaded it.

It sounds like you have an EEPROM reasserting the original program on a power loss. You need to find the function to update the program on the EEPROM.

This is only a guess, however, without all the information, it is hard to tell.

David