I am trying to control 12v Water pump using Arduino. From multiple forum threads, I have managed to run the pump using a N Channel MOSFET (attached diagram). However, the pump sometimes struggles to turn on, I can see it try to make a turn of the rotor and then gives up. Looks like there isn't enough "umph" to turn the pump. When it does start to work (Somehow manages to do a few times), it seems to work flawlessly.
I am rather new to this, and was told to use a capacitor, but not sure what sort of capacitance I should be looking for?
That's why to use a capacitor - to provide extra current at turn on above and beyond what the
supply can give (otherwise you'd need a much bigger supply).
Since this is 5A motor you'd need a lot of capacitance unless the startup is only a few milliseconds.
10,000uF would give you 10A (for instance) for about 6ms until the supply droop was down to
6V. If start up takes half a second, this gets prohibitive (10,000uF is pretty large anyway)
Hi,
I hope that fritzy diagram is not how you have it in real life.
Can you post a picture of your project please.
I can see it try to make a turn of the rotor and then gives up
If you havea 5A motor your wiring, in particular your gnd wiring should be able to handle the current.
If your motor stalls with 5A and nothing smokes or fuse blows, then I'd say you may need to look at the size of your wiring.
