replacing plc 2-20 with plc 2-30

[Lsocrat]

I have a plc @-20 in my factory where i cannot anymore upload the ladder program . . I Have in front of me a plc 2-30 .. Can i replace it ? can i upload the Program Without Further additions or Change.
please advise

 

[joseph_e2]

When you say you "...cannot anymore upload the ladder program.", does that mean it's full and can't handle more code or that there's something going wrong and you can't get the program out of it?

Note that there's some ambiguity with "upload" vs "download" with different software platforms reversing the direction of the transfer towards or from the PLC.