As a kid I used old refrigerator compressor motors as compressor for pumping air in bicycle tires. One needed a big capacitor, others do I believe some other trick to get started form just normal single phase 230V 50 Hz. But never really looked at it. I know my current refrigerator and freezers do not have electronics, I mean they do not have softstart or so manipulating the sinewave power or so. I just see very high power peaks when they start. A drill for example has softstart and reacts unstable if there is a lot of 'pollution' on the grid, for example 3-phase electric welding. It is fused with 3x 16A, slow (type C AFAIR) so higher peaks can happen. If 120V, it might be worse. TRIACs I have are 600V I believe, none died yet, but they get very hot, that is how it is.Around here refrigerators seem more susceptible to power glitches than any other device. So far one casualty and another that started working again after unplugging and then plugging back in. To me it seems like the compressor somehow jams, but maybe it's the electronics.A refrigerator is a 'buffering principle' a sort of buffering negative heat (lowering entropy), the compressor/motor does not run all the time. If you want to be online on the internet at least better than 1 minute offline gaps for example, it is different.
I am thinking to build a circuit to get an unused freezer stay cold enough 24 hours; In the night, compressor off and when enough solarpower, start the motor and extra cooling. Monitor with DS18b20 via flatcable inserted, the ESP microcontroller can stay outside.
Main grid is associated with a lot of issues, so for things that just need DC and less than 50V, I have based powering around a car battery (lead-acid). With about 1 hour no grid-power per year on average where I live, that car battery does get almost no charge cycles. It is very convenient to have though, as I do changes to electric installation every now and then, you want to have computers/PoE/NAS/internet etc just keep on running.
Statistics: Posted by redvli — Tue Aug 05, 2025 7:01 pm