I had an old Microwave Oven and decided to salvage all useful stuff from it .
It had powerful magnets , limit switches , temperature switches , heaters ,motors , fans , screws , piezoelectric tweeters and lots of wires andconnectors.
My favorite and best thing I 've got from it is the turntable motor.
I found that this motor is a powerful generator so I decided to make a Mobile Phone Crank Charger with it.
This motor is the unknown soldier in the Microwave oven that slowly turns the big glass plate inside the oven and over it all your food and stuff gets the waves and heat from all sides.
You can find many instructables and websites talking about safety precaution before opening the Microwave Oven.
Here I will show you my experiment with the turntable motor.
Step 1: Technical Background
The Microwave Turntable Motor can be a powerful generator if you could turn its rotor.
Actually , if you could turn the rotor by your hands while touching the Motor terminals you will get a painful ELECTRIC SHOCK ...... SERIOUSLY......
I have measured the induced voltage from the motor while cranking its knob and it outputs more than 400 Volts on AC Volt scale.
When I connect the output terminal to a Diode , it measures more than 200 Volts on the DC Scale.
But this voltage is not steady as it drops as soon as you move your hand turn the motor knob once again.
That large volt output compares to the small output current ( less than 20 mA ). It hardly lights an LED.
So what makes that motor a strong generator ?
I searched the web to see if it happened to any one else as it happened to me for the first time before I knew it.
I searched Google " Microwave motor electric shock " and I found a video showing a guy who opened the motor to know what makes it generate this electric shock.
The motor has a permanent magnet as a rotor and a thin Copper wire wound on a plastic reel as a stator.
Also , the rotor is coupled to some plastic set of gears to reduce the motor speed and increase its torque.
This motor is a high torque motor. It can rotate the big glass plate and on it all your food and dishes.
When you connect the motor to its nominal operating voltage supply ( 220 Volts ) it rotates at 6 rpm . Very slow so that no food gets spilled and all the contents get uniform heat distribution inside the oven.
Step 2: Material and Tools
The Microwave Motor
Metal Rod ( about 20 cm )
Two Crocodile Clips
Standard ( 220 Volts input ) Mobile Phone Charger of any kind.
Step 3: Making The Crank Rod
Using the Pliers, fold the metallic rod so that it makes a hook to the motor knob.
Then fold the other end of it to grab it from this end.
Step 4: Crank your Phone Charger
Now connect the motor with its crank connected to a couple of crocodile clips then connect them to a standard mobile phone 220 Volt charger at its input terminals.
Safety Precautions !!!!
Be careful not to touch either the motor , the charger or the crocodile clips terminals. You 'll get a bad electric shop.
It will not kill you but it is really painful and it hurts.
Now turn the motor using the crank rod while connected to the the phone charger and connected to the phone itself.
You can see that as you are cranking the motor the phone is charging.
Thank you for visiting.