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Does a 12V DC motor output DC current? ? Answered

I am doing a science fair project that involves a solar panel, connected to a charge controller, connected to a 12V battery, connected to a switch system that can either go to a flywheel with a 12V DC motor or straight to a DC to AC inverter which leads to light standard light bulbs. The system worked (light bulbs lit) when I connected the panel to the controller to the battery to the inverter. However, when I had the battery power the flywheel and then have the flywheel output its energy to the inverter, the inverter shut down and would not work (red alarm went off). The flywheel is producing more than 10V (starts at about 11V) for at least 30 seconds, and the inverter's low voltage shut down in 10.5 plus or minus 5 volts. So why doesn't it work? Is the inverter messed up or is the flywheel outputing AC power? Also, when I connected the solar panel to the charge controller to the flywheel, the charge controller completely shut off. Are charge controllers not able to be directly linked to motors? And if I tried to directly connect the solar panel (which has 20V) to the flywheel (with a 12V motor), without a charge controller in between, what would happen?


The inverter NEEDS really good quality DC, your flywheel output will be very rough DC and the inverter shuts down.

A charge controller limits the current output to protect the batteries, a motor is an illegal load for it.

If your 20V panel can supply enough current to run a 12V motor, the motor will run.

I suspect the cut off for the inverter is a little higher then quoted, and higher then it says, just try a little test, put a large value capacitor across the motor, the higher the better > 4700uF let this charge up with the DC supply, monitoring the voltage across the capacitor, switch over so the motor now feeds the inverter, but do it quickly, if the inverter briefly fires up, because of the higher charge in the capacitor, then the shut down voltage of the inverter is higher then stated.

Incidentally, its "DC" or "Direct Current" it can't be DC current, which is Direct current current.....

What kind of dc motor do you have?

Does it have brushes?  If so then 99% sure it outputs dc.  O you have the polarity wrong on the generator connection to the inverter.

Is it a stepper or brushless?  If so then 99% sure that it outputs ac.