Hey, everyone. Could someone steer me in the right direction on this?
I'm to using a NANO to control an electromagnet, both powered at 12v, and I want to use the same power converter for both. Separately, the NANO circuit draws around 200mA and the magnet does what I need it to do with less than 400mA, so a 600mA converter should be enough to power both, correct? My problem is that, as the inductor has such low resistance, it's drawing way more current than it needs (close to 1A) and powering off the Arduino. The whole thing works fine with a beefier power supply (bench PSU current limited at 1.2A), but I want to make it work on a cheaper, ~800mA converter. Should I try and limit the current the inductor can draw? How to go about that? Slap a chonky (decoupling) capacitor parallel to the Arduino, instead? Seems to me that'd be fruitless, as the magnet stays on for 1500ms at a time, more than enough time to deplete the cap. (Related topic forum.arduino.cc/index.php?topic=296115)
Get a pwr supply of some 1.5 Amps, or more. Or get another electromagnet that needs less current.
Your E-magnet pulls 1 Amp. You can try and add a powerresistor of the proper value to lower the current and see if that magnet does any useful job.
How much voltage does the electromagnet need to operate? If it only needs 8 V, you can put a resistor of half the electromagnet's resistance in series, and it will draw only 2/3 the current. Or use an 8 V power supply, needless to say.
Incidentally, if your Nano is drawing 200 mA and you are powering it from 12 V via "Vin", you are going to have some serious problems, You should be powering it from 5 V.
you could use a constant current source to drive the solenoid, although the additional cost of the constant current source would probably be the same difference as just getting a supply that can handle what the solenoid takes.
study "commutating dode", also known as "switching diode". bottom line: you need a robust diode across that solenoid, reverse polarized, with a very high PIV - peak inverse voltage - rating, to shunt the huge spike of reverse polarized voltage that comes when power to a coil is cut. this is the fat blue spark you see when you disconnect a DC power source.
