The purpose is to show a small scale (for the classroom) example of what would happen if something like a small battery operated fan were running on AC instead of DC. I would like to show the fan going in one direction, then change direction, as the current changes direction. Is this even possible? From my limited understanding, most items that use an AC source, but need DC power, have rectifiers to keep the current flow going in the same direction. I want to demonstrate what would happen if there was no rectifier.Thanks.
no longer sufficient information to respond to. Or in different words, it relies upon ... AC motor technologies is so quite stepped forward, it incredibly is often greater value-effective to run than DC. The assessment with the lighting fixtures fixtures won't artwork, it relies upon on the completed capability of the autos and the lighting fixtures fixtures. A 20 watt mini-lathe will value much less to run than a financial organization of one hundred watt lighting fixtures fixtures, and vice versa. And the place are you going to get the DC 220 volt from? I in no way heard of that for a compressor or lathe, are you particular it is DC? Does it say something like 50 Hz or 60 Hz, or does it have unmarried section or 3-section? those are all AC words. maximum DC autos are 12 V or 24 V. those I even have seen for 220 V are very small.
Do not try to operate DC devices with AC current without a converter. It could be dangerous. Also, in the USA, current changes directions 60 times a second. You can't see anything change directions at that speed. You would probably just see a blur. Don't experiment with electricity unless you are certain about what you are doing. Oh yeah, and don't operate AC devices with DC either, for the same reason. There are other ways to demonstrate the difference. I am glad you are curious about the science of electricity, or any kind of science. Stick with it. Just be careful.
Most AC motors now a days don't even use rectifiers, they just use AC induction motors which can only run on AC because the magnets rely on the alternating field . Maybe some real small motors use AC that runs through a rectifier...possibly alarm clock motors. But the problem with taking the rectifier out is one of physics. In AC current the alternating current switches direction 60 times EVERY SECOND. So for a rotating mass of a fan motor or alarm clock motor to switch direction every 1/60th of a second isn't going to happen. Now you can take your battery operated fan and run it on AC just for a moment, but the DC motor would not run on AC since the magnetic field in the field coils would be reversing direction 60 times every second, so the motor would just sit there and start getting hot instead of moving. But at least it would show them you can't interchange AC electric with DC electric, at least in motors. It would work with light bulbs though. If you run DC or AC through the light bulb they both will turn on the light due to the resistance of the circuit (and no moving parts to change direction). Now to finally answer your question, you could put AC current to a small DC motor as long as you put a diode (rectifier on one of the two lines feeding the motor. The rectifier would cut off the negative amplitude of the alternating current. To reverse the current you would have to reverse the wires going to the diode with the other hot line. The point is one of the two wires going to the DC motor must have a diode in it's path. You don't have any diodes in there , then the motor won't move, it will just hum and get hot Also be prepared for short circuits, sparks and blown circuit breakers
