The little logo in the bottom corner has something I can't make out and then 'Switzerland'
I don't know if that's any help (So the A and E would actually be Swiss Deutsch... Maybe ).
Anyway, I'm off to see it on Friday with plans of convincing the owner to ceremoniously dump it (but it would be nice to suck the code out first although not essential).
Apparently it does still work, just not the way the owner wants it to.
From what I can find out, if it's the Biovator PLC016 it's over 30 years old That's pretty impressive for a PLC (especially considering the atmosphere it's in).