Stepper Driver stops working?! What Happened and Why?!
Over the years I’ve done many projects and tutorials using Stepper Motors and of course that includes Stepper Drivers.
Stepper Drivers, like the Easy Driver, are required to drive Stepper Motors since the Arduino itself cannot provide anywhere near enough current to drive them.
Now of course over those years of playing around with Stepper Drivers, once in a while one of them would just stop working for no apparent reasons…
So today let’s have a look at why a Stepper Driver can just ‘give up the ghost’ and what we can do to avoid it!
EasyDriver Stepper Driver
These are Amazon affiliate links...
They don't cost you anything and it helps me keep the lights on
if you buy something on Amazon. Thank you!
WHAT "KILLS" STEPPER DRIVERS?
A couple of things can lead to a Stepper Driver not working.
Now for today we will remove the possibility of the Stepper Driver being bad and just plain not working from the start.
Also let’s remove the possibility of the Micro Controller (i.e. Arduino) being responsible,
unless you gone and wired the Arduino to Stepper Driver terribly wrong, like connecting the 5V from the Arduino to the GND pin on the Stepper Driver, there’s no way it can be responsible for a dead driver.
So what are we left with?
Fist thing to consider is the power supply to provides power to the Stepper motors through the Stepper Driver.
Most Stepper drivers have a range of voltage that they can operate within.
For example the Easy Driver can take voltage from 6 volts to 30 volts.
If you set the power supply higher than 30 volts that can kill a stepper driver pretty quickly.
One piece of advice I would give you is:
Before connecting your power supply to your project and turning it on…
Disconnect the power supply from your project, make sure that the voltage is set to the right amount, turn it off, and ‘then’, connect it to your project.
That way you are sure not to feed to much voltage when you turn on your power supply.
If your power supply is malfunctioning and providing move voltage than it’s supposed to that can do it as well.
It’s always a good idea to check the output of your power supply using a Multimeter once in a while to make sure it’s outputting what it’s supposed to.
Ok so you’ve checked the power supply and it’s fine, so what else can kill a stepper driver?
THE MAIN CULPRIT!
Ok so now we get to the likely reason why Stepper Drivers die…
The sure way to kill a Stepper Driver is to connect or disconnect a Stepper Motor while the Stepper Driver is powered ON.
You see Stepper Drivers provide current to each coils of a Stepper Motor and those current are switched back and forth to make the Stepper Motor rotate.
So when a connection to one of the coils gets disconnected it creates a spike (current/voltage) that gets feed back to the Stepper Driver and can cause failure.
Now, of course better built Stepper Driver have protection against this, and might be able to tolerate it, but the simple and cheap drivers we use as hobbyist might not be able to and just burn out.
So knowing this what do you think is the most probable cause of Stepper Driver failure in a project?
The Wiring and….. The Breadboard!?
Let’s talk first about the wiring!
When prototyping a project, you’ll be most likely using the type of wires you see in the picture above.
Those wires are cheap and easy to find almost anywhere (amazon, aliexpress, etc…) commonly named ‘Dupont wires’.
It’s a good idea to check the condition of these wires once in a while to make sure that they are not damaged or broken, which can cause failure of a stepper driver.
But the main culprit that can lead to damaging your stepper driver is the BreadBoard!
When connecting the Stepper Motor to a common Stepper Driver like the Easy Driver you will probably using a BreadBoard to make the connection between the two.
Common BreadBoards are made to accept solid core wire of around 0.6mm or 24AWG size to guarantee a good and reliable connection.
But most wires coming out of the Stepper Motor are not solid core, but made of multiple strands of small wires wrapped together, and result in a wire size smaller than what the BreadBoard is expecting.
So even if you think the stepper motor wire fits in the breadboard and seems to be working when doing some testing… The slightess movement of the breadboard or the stepper motor wires, might result in a momentary lost of connection and lead to your stepper driver being damaged.
So although it seems tempting to just plug those stepper motor wires directly to the breadboard, DON’T DO IT!
AN EASY SOLUTION!
Here is what I started to do to prevent damage to my stepper drivers.
All the stepper motors that I use when prototyping projects have Dupont wires soldered to the end.
This way when connecting the stepper motor wires to a breadboard I can be positive that the connection is pretty solid.
Also when I apply power to the project, I try to make sure not to move the breadboard, stepper motor, or anything else that might raise the chance of something getting disconnected.
Since I started taking those steps when working with stepper drivers, I haven’t had a stepper driver malfunction.
So taking just a bit of time to solder the proper size wire to the stepper motor and being careful not to move your project when the power is on, just might save you some money in the end.
Thanks for stopping, and hope to see you again soon!