Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
A resistor in series with the fan limits the current so the fan might not start running.
Use a proper 12V power supply.
No, the capacitor prevents the voltage across the 12V fan from spiking up to 20V as it runs.isnt that why the capacitor would be added?
Your calculations are correct. I though you were using a standard 80mm or 120 mm fan. A fan of single digit watts to cool a computer. This is a 10 watt fan.alright im rather confused at the explanation of the ohms law stuff.
The fan alone didn't create the spikes. The 18 volt peaks came through the resistor when the motor drive transistors shut off and there was briefly no load after the resistor. This happened apx 100x a second as the fan was running. In snobrder27's case, they will be 20V peaks across his 12v fan. The peaks will not be there if the fan is run directly from a 12V supply. That is why I added the capacitor to the crummy design.If a 12 volt fand creates 20 volts spikes, that is perfectly normal and acceptable operation. No acceptable fan will create spikes that destroy itself.
Good. Sometime in the future (and look forward to this), you will make a math error and see smoke. We call that fun - or learning from your mistakes. Appreciate how easy using math is to design simple solutions. And why a solution requires both the math and a successful test before that solution is complete.After wiring the 10 watt 10 ohm resistor into the circut the fan runs perfectly.