Script for logging voltage using UPS device and Network UPS tools

voltage_logger.sh

#!/bin/bash

previous_filename="none"
previous_voltage=-1

while true
do
    filename=$(date "+%Y-%m-%d")
    upsinfo=$(upsc powercom 2>/dev/null |grep 'input.voltage:')
    voltage=${upsinfo#input.voltage: }
    voltage=${voltage%.0}

    if [ $previous_filename != $filename ] || [ $voltage != $previous_voltage ]
    then
        date=$(date "+%H:%M:%S")
        echo -e $date"\t"$voltage >> ~/powerlogs/$filename.csv
        previous_filename=$filename
        previous_voltage=$voltage
    fi

    sleep 1
done

Requires:

1. UPS with data channel
2. https://github.com/networkupstools/nut/ installed and supports UPS