We finally calibrated the holding tank
(ultrasonic gauge connected to BlueSea monitor
So we know that the tank is empty, and the BlueSea monitor
indicates that the tank is empty. Check.
The high alarm
is set to 80% and the low alarm
is off. Check.
Problem: When we turn off power to the "instruments" at the DC panel, the holding tank
goes from 0% to 100% and the alarm sounds. When we turn the instruments back on, the value goes to 0% and the alarm stops.
I am not sure if the instruments were powered when I did the calibration.
What should I be looking for? The system was installed by the PO.