Is there a trick to this? I imagine for the freezer you might be able to place a small spoon on top of a bowl of frozen water, and if it turns off for a period of time and turns back on, if it was off long enough the ice could melt and allow the spoon to lower into the water. Of course the freezer compartment has much more temperature stability, but for the fridge, there’s a much greater susceptibility for food spoilage if the temp rises above 40F.
Almost every device I have with a clock does not have a battery backup. They’ll either flash 12:00 or --:–. I’ve had my clock radio since 1977, so no battery there. The VCR isn’t much more than a clock now. The oven is brand new and no battery there either.
Happens all the time where I live; let’s see, digital clocks flashing, stove display has a “PF” on it (power failure), microwave digital read out blank, and when you turn on the TV, there is a message to “set up” our DTV like we just got it, but you don’t really have to go thru the motions, that message goes away after a minute. But just saying, in the world today, you don’t have to be a rocket scientist to realize that the power flicked off!
A bag of ice cubes works easier than a spoon. I used that all the time for the travel trailer fridge/freezer.
Otherwise…depends on what you want to spend. There are temperature loggers that you can purchase that will record a temperature on a scheduled basis, and usually include alarm settings if the temperature gets out of a specific range. They’re not cheap, though.
Oops. Now I get it. You want to know about the temp change in the freezer.
What Mavyn said.
if the dinosaurs have escaped their enclosures i figger the power went out and the fences lost their electrification. otherwise i’d check to see if a zombie richard attenborough is eating alla my ice cream.
The easiest way is to get an alarm clock without a backup battery. Anytime the electricity goes out, the clock will reset to 12:00 and usually stay there until you set it up.
Actually I’ve found that a number of digital clocks start running once power is restored, so it is easy to figure out when power came back on…provided you didn’t go to Wheaton High School for math.
As for leaving a spoon on ice, the freezer would need to defrost and really warm up before the spoon would go lower. Remember - the spoon was cold too.
I would think something like a popsicle or ice cream sandwich would work well for detecting if it the freezer had defrosted/restarted. Neither one would assume the original shape upon refreezing.
so just check the milk or eggs. if they’re spoiled the power musta gone out.
I log into one of my UPS units, they will say how long the power was out.
Also, the gas stove shuts off the gas (or so it thinks, I over-rode that function). You gotta press ‘start’ to get it to stop flashing…
And, my home has two timers (whole house fan and LV lighting), they will be off time.