10 min / 60 = 0,166 * 1000 = 166Wh
3 min / 60 = 0,05 * 1500 = 75Wh
20 min / 60 = 0,333 * 1800 =599Wh
180 min / 60 = 3 * 60 = 180Wh
A refrigerator use power when it works its way down in temperature, when it has come down in temperature it turns off the compressor. My fridge is using about 5 amps when it is running at first but when it is down at the right temperature it stops and only kicks in now and then. It only works to maintain the temperature that is set. Depending on how much I have in the fridge, the time to get down in temperature takes about 15 minutes. You can use an ice clamp to help it drop in temperature to save power. My fridge uses this formula to calculate what power it draws per day.
Formula: Current draw x average running time* (48 W: 12 V = approx. 3.75 A)
Example: 3,75 A x 22 % (22% of the time) 10W
Amperage: ‹ 1 Ah / h, ‹ 24 Ah / day
And this is how I believe my fridge is running so the formula is correct.
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