Originally Posted By: julf
Originally Posted By: K447
APC tweaked the port configuration over the years, so not all models had the exact same port configuration. And I think there were different versions of the serial cable too.


Yes, looking at the apcupsd web pages shows there was quite a variety of cables... Until now I was convinced the cable I was using was the original cable that came with the unit, but I can't see any product/manufacturer name or product number on it, and it is supposed to be embossed into the plastic.
You can check the cable pin connections using a multi-meter and a thin paperclip. If it is a standard serial cable, the meter will tell you.

Without checking the Interwebs, I recall that the genuine APC 'serial cable' uses only a few pins, several pins will have no connection.