If you’re looking to monitor an APC USP (many of the latest models have a USB port for monitoring) this is the best walk-through I’ve found:

http://www.anites.com/2013/09/monitoring-ups.html

Thanks to Kenneth Burgener for his great write up.

Being able to query the UPS or perform actions based on Power Off/Power On state is fantastic.

$ apcaccess 
CABLE    : USB Cable
DRIVER   : USB UPS Driver
UPSMODE  : Stand Alone
STARTTIME: 2016-03-09 09:10:19 -0700  
MODEL    : Back-UPS ES 550G 
STATUS   : ONLINE 
LINEV    : 122.0 Volts
LOADPCT  : 6.0 Percent
BCHARGE  : 100.0 Percent
TIMELEFT : 107.5 Minutes
MBATTCHG : 5 Percent
MINTIMEL : 3 Minutes
MAXTIME  : 0 Seconds
SENSE    : Medium
LOTRANS  : 92.0 Volts
HITRANS  : 139.0 Volts
ALARMDEL : 30 Seconds
BATTV    : 13.5 Volts
LASTXFER : Automatic or explicit self test
NUMXFERS : 2
XONBATT  : 2016-04-04 06:36:26 -0700  
TONBATT  : 0 Seconds
CUMONBATT: 16 Seconds
XOFFBATT : 2016-04-04 06:36:34 -0700  
LASTSTEST: 2016-04-04 06:36:26 -0700  
STATFLAG : 0x05000008
SERIALNO : 4B1414P00197  
BATTDATE : 2014-03-31
NOMINV   : 120 Volts
NOMBATTV : 12.0 Volts
END APC  : 2016-04-10 09:13:05 -0700