I'm trying to get my NEMA 17 stepper motor working via Arduino.

As a power supply I'm using a 24 V DC power supply adapter, 24 V 2 A 48 W AC to DC converter transformer 100~240 V AC input with 5.5x2.5 mm DC tip.

I cut off the DC tip to expose the VDD and GND wires. I hooked them up into my breadboard and when I plugged it in the wires hooked into the breadboard sparked and fried some of the wires on the power supply (like the positive red wire had some copper threads which got burnt off.) The power supply also had an LED light when plugged in, which is no longer working.

I'm just trying to understand what I've done wrong. I think the GND and VDD wires touched each other, but wouldn't this just short circuit instead?

  • 7
    \$\begingroup\$ You shorted the power supply which killed it. It’s dead Jim. Time to get a new one. \$\endgroup\$
    – winny
    Sep 17 at 19:01
  • 1
    \$\begingroup\$ Add a link to the datasheet (not an Amazon ad link) for the power supply. Then we can check to see if it has internal short-circuit protection. \$\endgroup\$
    – Transistor
    Sep 17 at 19:06
  • 1
    \$\begingroup\$ The product advertises "over-current protection," but it also advertises silly things like "over-circuit protection" (not a thing) and "grounded protection" (impossible because it doesn't have a grounded, 3 prong mains plug). It appears to be junk. Unfortunately there's an awful lot of this class of junk on the Interwebs, much of it from China. \$\endgroup\$
    – TypeIA
    Sep 17 at 20:35
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    \$\begingroup\$ That's an Amazon ad link and, as usual with Amazon, there is no datasheet. "No datasheet? No sale!" \$\endgroup\$
    – Transistor
    Sep 17 at 20:37
  • 1
    \$\begingroup\$ In the description, it says: "But if draws more than 2A, only 2A will be supplied and power supply will be damaged soon. NEVER OVERLOAD!" I am pretty sure you are not supposed to short it. \$\endgroup\$
    – Wjx
    Sep 17 at 20:40


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