Accidentally set 50Hz for US Home Consuption and things seemed to work - mostly

OffGridInTheCity

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I have a 2nd AIMS Pure Sine Wave Inverter on the way so I moved the 1st one to make room. These are 174lbs so they take serious pushing. In the process, I accidentally toggled the dip switch from 60Hz to 50Hz. These dip switches are exposed at the control end - maybe they need a cover.

In any case, when the system wasre-energized, I noticed after 2 days (14hrs of operation!)
1) The Microwave made a new noise - like the fan going bad... but only when the Inverter was on.
2) That the clocks lost over an hour a day instead of a few minutes. **Bingo, this tipped me off, finally**

I can't believe I did this (and a good lesson when re-positioning heavy inverters - re-check exposed dip switches)but I'm surprisedthat things ran at all and that i didn't blow everything up.

Can someone comment on why things worked at all? I presume that I put my home equipment at high risk by doing this? By home equipment I mean - computers, TV, refrigerators, hybrid hot water heater, furnace fan, microwave/kitchen appliances, and other (lights, tools, chargers - including OPUSs)
 
Most devices these days are designed to accommodate both 50hz and 60hz. They'll say something like 50-60hz on the input labels. Those devices won't care - the Opus, probably your computer, etc. Pretty much anything with a plug transformer, like your Opus or cell phones, probably even say 110-220V.

The only thing it really hurts is the inductive-based loads and anything that uses the hz to keep track of time, which you've noticed :)
 
Agree with mike. The only thing that it really hurts would be time based things, like clocks, the microwave, etc.
The microwave may have had a funny noise because of the electric motor that turns the turntable. It might not like 50Hz so much as it is an induction motor

Induction motors in the US are tuned for 60Hz. These include the aforementioned turntable motor, ceiling fans, possibly washer/dryer motors, blower fans, and the like. So when they are ran at 50Hz instead, they usually just hum. And the faster they spin, the louder they hum. Sometimes if the motor is set low enough speed, it's possible to lock the motor in place and it just sit there and buzz until it's given a bit of spin assistance.
These types of motors will work fine in short uses. But if prolonged, could actually burn the motor up over time as it does make them hotter. This is the same thing that happens running these devices off a modified sine wave instead of pure sine wave.

At least you had a messenger let you know something was up ;)
Ohh, if you have any kind of timer, like for lights, water heater, irrigation, you might wanna go check them as well to make sure they are set to the proper times.
 
+1 to all Korishan & Mike's comments above.
In addition to the heating mentioned, running at 50Hz vs 60Hz will make induction motors (ceiling fans, washer/dryer motors, blower fans, water pumps) run slower, ie 5/6 of the usual speed.
 
Basically digitall converters will not care since they switch it anyways to higher frequenzy while transforming.

Analog devices like old lampa and Transformers Arent optimizers for it and Will flickor or make Noice and in worst case burn since they Arent optimizers for that frequenzy.

Thats what you heats and the clock based its time on it and thats why it went slower.
 
The main issue with running equipment at 50Hz that was designed for 60Hz is where inductors are designed for 60Hz and the lower frequency results in higher losses and heating. Some equipment if designed for 60Hz and then run 100% loading on 50Hz may end up overheating and burning out.

This impacts equipment parts like transformers and some induction motors. Transformers are effectively de-rated when running on 50Hz by around 16%.

The reason is the design flux density (magnetic field) is impacted by the frequency and you need more turns per volt on a 50Hz transformer compared to a 60Hz unit. Higher the frequency the smaller the transformer (hence high frequency inverters weigh very little as they operate in the kHz range for the step up stage).

Everything else which is a solid state power supply does not really care as they typically take a rectified DC supply as their starting point, so you could probably run them between 40Hz and several kHz. The only issue is the lower the frequency the more energy that is transfered in the peak of the voltage waveform, too low frequency the peak current get's too high.

Summary : don't use 60Hz transformers on 50Hz...
 
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