arclance - 2012-08-15

This was reported two years ago in v1.8.1 though it was never fixed.
https://sourceforge.net/tracker/?func=detail&aid=3083859&group_id=143975&atid=757308

If you build from source you could try using the debian patch for apcupsd.
http://patch-tracker.debian.org/patch/series/view/conky/1.9.0-2/fix-apcupsd.patch

You can also get the same information using "apcaccess status" in a script.