My A4988 caught on fire

Other Hardware Motors, Mechanics, Power and CNC
1

I was trying to get my A4988 stepper motor driver to work. I was supplying it my workbench psus max current (10.23A) and only 18v when it can take up to 35v. I think the 10A might be the issue but when I plugged it in, it was only drawing less than 1 so I assumed it would be fine all the way cranked up.

I’ve worked with A4988 drivers in the past but used a desktop pcs power supply and a workbench PSU so I couldn’t change the current and it worked perfectly before

Please let me know if that is my issue also I sent a video of it catching fire in the link

https://drive.google.com/file/d/104G4NkBK7_QIY0-rTzulfbngraf0r28C/view?usp=drivesdk

2

Did you set the current limit ?

3

Don't. Read datasheets!

4

If you mean the screw thing, I thought that was to limit the voltage not current, if it’s for current what do I probe with multi meter to see and change the value. Also what setting on multi meter

LarryD 5
6

Oh, my. Sadly, you are a member of the elite Magic Smoke Club:

image

I suggest back-to-basics:
Watts (power) = I * I * R

I understanding the formula Power loss= I^2 R | Physics Forums

7

I don't see a stepper connected to the driver, just an LED. The driver probably ramped until it cooked itself.

8

You adjust the pot on the driver without a stepper connected.

9

If you look on the Pololu site on the page for the a4988, under one of the tabs there is a video showing how to set the current.

The power supply max current has nothing to do with it as long as it exceeds the stepper driver current.