Install apcupsd

pacman -S apcupsd

Edit /etc/apcupsd/apcupsd.conf:

UPSNAME SMART750
UPSCABLE ether
UPSTYPE pcnet
DEVICE <ip>:device:<password>
BATTERYLEVEL 10
MINUTES 10

Enable service:

systemctl enable apcupsd.service
systemctl start apcupsd.service

Test:

apcaccess status