Running a 12V 2.2 A DC Water Pump with ARDUINO

Using Arduino Project Guidance
1

Hello all,

I have a few questions on a project I am attempting to complete. I have looked up quite a few tutorials and think I am aware of what I need for the project just I should do my due diligence and double check with you guys since you definitely know more than I.

The sketch I have come up with is attached for you to see. So I am looking to run a 12V max current 2.2A water pump. Is it feasible to say I could run this pump at 10 or 20 second intervals every 10 minutes for 24 hours? I only need to turn the pump on and off so was probably going to use the digital pin but could use the PWM pin number 9 in case I want to ease the pump down.

I am pretty sure I need a flyback diode to counteract the reverse current from the pump shutting off I just don't know which one would be appropriate and successful. I also don't really understand how to set it up making sure the polarity is correct.

The MOSFET I am using is a RFP30N06LE 30A 60V 0.047Ohm Logic Level N-Channel Power Mosfet TO-220 ESD which I think will work as I looked at the spec sheet.

Any insight or suggestions you may have is greatly appreciated. Also any questions you may have feel free to write back. Thanks!

arduino sketch.jpg
arduino sketch.jpg576×1024 133 KB

arduino sketch.jpg
arduino sketch.jpg576×1024 133 KB

2

Yes, you should have a diode, one capable of handling as much current as the motor draws. You have it drawn correctly.

I would also use a series resistor between the Arduino pin and the gate to limit the rush of current from the pin into the gate capacitance, which looks like a short to +5, or Gnd, as the output changes.
5V/.035A = 142 ohm, so a 150 ohm resistor would be good.
And add a 100K to Gnd from the Arduino pin, will ensure the gate does not float during a reset, or power loss, or anything else that could let the pin float while Arduino does not drive it.

How often you run the pump is up to you. Is it rated for continuous operation? Then periodic on/off would be okay. Otherwise, read its spec sheet and see what it says.

3

So would the drawing look like this?

new sketch.jpg
new sketch.jpg1024×576 120 KB

4

No, your 100K resistor would be attached between pin 9 and ground (or Gate and ground) Doesn't matter.