I can't figure out the numbers for this allarm. If it's in minutes, hours, seconds. I put in 1440 for a minimum for 24h but it's showing me 0.00h I'm at 250h and last night when on battery power we dipped to 81h. I'm putting in 90 for low now and 100 to turn off and it still shows me 0.00h and throws the alarm. What's the trick here?