I have a group of electro magnetics that receive oscillating current via Arduino pwm and powered by three L298N. Currently each group work as intended separately, when supplied with a 12V voltage, however they couldn’t work together. How to power three L298N motor driver with each getting a 12 v power supply?
Methods I’ve tried:
Connect three drivers together with 12 v external supply -> results: zero to none voltage in all drivers;
Connect three drivers together with 24 v external supply -> results: around 5v in all drivers;
Connect a step up voltage adapter to each driver-> result: initially each driver receive a 12 v supply, after Arduino board plugged in, voltage dropped to around 5 v for each driver;
Haven’t tried:
Get three 12 V power supply cable and plugged them to three drivers separately. I’m trying to avoid this scenario.
The supply has to deliver the current taken by all magnets. Check the supplied voltage with all modules connected.
Perhaps jumpers on the driver boards are not correctly set?
Do the drivers support the required current?
Are all PWM signals set to 100%? You can test each driver with the Arduino disconnected and all inputs connected directly to LOW/HIGH level.
The L298 dinosaurs will drop up to 4V from the supplied voltage, converting the drop into unwanted heat. You may be better off with more modern (MOSFET) drivers.
For more detailed analysis a symbolic circuit diagram is required. No Fritzing please.
Not sure if this will make any difference, but try removing the 12v jumper and give the boards 5v input externally (you need to remove the jumper if the voltage is higher then 12v and then provide the 5v from another source).
This is how I'm running my L298N on 24v power supply.
Your electro magnets will demand a large amount of in-rush current when turned on. I'm suspecting your power source isn't capable to provide the required current.
While measuring the voltage and current At The Power Source, turn on the 1st magnet, then the 2nd. If 2 work, the current increased and the voltage is still correct, turn on the 3rd. Did the voltage drop?
If the voltage didn't drop, measure the voltage converter outputs. Keep moving down until you find where the voltage drops.
Correction: I didn't use PWM on Arduino. L298N drivers signal pins only receive High/low signals.
The reason why I used L298N for electromagnetic is because I need to change the current directions to get magnets change poles . I happened to have leftover drivers for DC motors from last project, which can change current directions.
Another thing that I tried was to connect the grounds of all drivers to Arduino ground, didn't solve the voltage issue.
@asdfwer11
The layout depicted in post No.9 looks reasonable.
I suggest some heavier gauge wire than the junky jumper situation (as shown in post No.1, lots of 'spaghetti' there)
Wire the 12V supply to a terminal strip and distribute to the L298 boards from there.
