I have a DC motor pulled from a cordless hand vacuum, powered by an AC adapter pulled from a laptop computer, and controlled (on/off) by a control board connected to my computer (USB). I will turn it on and off by pressing a key on my computer. Please see the below diagram. I can get the circuit working for a like a minute. But, after being on for about a minute (that is, the DC motor running for a minute), it fails.
I have fried this circuit about 3 times already. The first time I fried the transistor because I did not attach a heatsink to it (was not informed that this is necessary). But, the second and third times I have fried this circuit, I am not sure what I am doing wrong. I am a total beginner and the components in my diagram are all based on someone's recommendation on another message board a few months ago.
Right now, when you turn on the circuit, the motor stutters. What I mean is, the motor moves in pulses like on for a millisecond, then off for half a second, then on again for a millisecond, then off for half a second, etc., etc.. At first, I thought I messed up the AC adapter, but I plugged it into the laptop (the AC adapter was from a laptop computer) and it is able to power up the laptop. But, if I take some wires and run them directly from the AC Adapter's plug straight to the DC motor (bypass the whole circuit), the motor still does that stutter like I described above. But, if I attach the original rechargeable battery pack that comes with the motor (remember, this motor was taken out of a cordless hand vacuum cleaner), the motor runs fine.
I forgot to also mention, the reason I thought the AC Adapter might be messed up is because took another AC adapter from a printer that is 16V and like 500mA and I connected that directly to the DC motor as a test. This AC adapter is "smart" in that it has this little green light on it. It tells you when power is going through it (I guess). Anyways, I think it is also has some kind of fuse or circuit breaker in it because when I plugged the AC adapter into the wall, the green light is on. Then when I run wires from the adapter's plug straight to the DC motor, the motor jumps to action for like a split second - and then the green light on the AC adapter turns off. If I unplug and then plug in the AC adapter again, the green light turns on again.
Does anyone know how to fix this?
I have a feeling - though not sure that I may need to use a better diode? I am thinking maybe I should use a 1A diode (Model 1N4004) called 1N4004? http://www.radioshack.com/product/index.jsp?productId=2036270
But, I also see that Radio Shack sells another diode that they sell a 3A diode as well (Model 276-1141). Would that be better? I guess more amps the merrier maybe? But they call it a "barrel diode" - not sure what "barrel" means here, so not sure it can be used. http://www.radioshack.com/product/index.jsp?productId=2062577
Also, do I need to change the resistor? I see a lot of people mention a 1K resistor on message boards. Should I use that? I see Radio Shack sells a 1K Ohm 1/4 Watt resistor (Model 271-1321). Should I use that instead?
Help!
I have fried this circuit about 3 times already. The first time I fried the transistor because I did not attach a heatsink to it (was not informed that this is necessary). But, the second and third times I have fried this circuit, I am not sure what I am doing wrong. I am a total beginner and the components in my diagram are all based on someone's recommendation on another message board a few months ago.
Right now, when you turn on the circuit, the motor stutters. What I mean is, the motor moves in pulses like on for a millisecond, then off for half a second, then on again for a millisecond, then off for half a second, etc., etc.. At first, I thought I messed up the AC adapter, but I plugged it into the laptop (the AC adapter was from a laptop computer) and it is able to power up the laptop. But, if I take some wires and run them directly from the AC Adapter's plug straight to the DC motor (bypass the whole circuit), the motor still does that stutter like I described above. But, if I attach the original rechargeable battery pack that comes with the motor (remember, this motor was taken out of a cordless hand vacuum cleaner), the motor runs fine.
I forgot to also mention, the reason I thought the AC Adapter might be messed up is because took another AC adapter from a printer that is 16V and like 500mA and I connected that directly to the DC motor as a test. This AC adapter is "smart" in that it has this little green light on it. It tells you when power is going through it (I guess). Anyways, I think it is also has some kind of fuse or circuit breaker in it because when I plugged the AC adapter into the wall, the green light is on. Then when I run wires from the adapter's plug straight to the DC motor, the motor jumps to action for like a split second - and then the green light on the AC adapter turns off. If I unplug and then plug in the AC adapter again, the green light turns on again.
Does anyone know how to fix this?
I have a feeling - though not sure that I may need to use a better diode? I am thinking maybe I should use a 1A diode (Model 1N4004) called 1N4004? http://www.radioshack.com/product/index.jsp?productId=2036270
But, I also see that Radio Shack sells another diode that they sell a 3A diode as well (Model 276-1141). Would that be better? I guess more amps the merrier maybe? But they call it a "barrel diode" - not sure what "barrel" means here, so not sure it can be used. http://www.radioshack.com/product/index.jsp?productId=2062577
Also, do I need to change the resistor? I see a lot of people mention a 1K resistor on message boards. Should I use that? I see Radio Shack sells a 1K Ohm 1/4 Watt resistor (Model 271-1321). Should I use that instead?
Help!
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