What resistance should I use in my 12V Solenoid+Arduino circuit?

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alpkan
 
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What resistance should I use in my 12V Solenoid+Arduino circuit?

Post by alpkan »

Hello all,
I am trying to control an Adafruit 12V large solenoid with Arduino. I am a beginner and I am following the instructions from this video (https://www.youtube.com/watch?v=Yh3TLXihUps&t=2s).

I have a 12V large solenoid (I think it takes around 1mah to work), an Arduino Uno, one Tip102 Transistor, one IN4001 Diode in my circuit, which I am powering with a 12V 1500mah power adaptor. I am getting confused with calculating the resistor I should use. The guy is using a 1K Resistor but his power adaptor is 1am (mine is 1.5am).

I was wondering if anyone can help me calculate what amount of resistance I should use. Thank you.

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adafruit_support_bill
 
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Re: What resistance should I use in my 12V Solenoid+Arduino circuit?

Post by adafruit_support_bill »

1K should work fine. The resistor is to limit the current through the base of the transistor. That is a function of the voltage from the control pin and is independent of the power source you are using for the solenoid.

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dastels
 
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Re: What resistance should I use in my 12V Solenoid+Arduino circuit?

Post by dastels »

The current rating of the power supply doesn't matter (as long as it's high enough). It's the current required by the circuit that does. That's the solenoid in this case.

See https://learn.adafruit.com/transistors- ... -s-2998944.

Dave

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