Thread: brand new dc-dc...big spark

The input of the Arise supply is protected via a fuse and diode if I remember correctly, so I doubt you killed it. Someone with electronics knowledge will be able to determine the problem in a few minutes, but a blown fuse is fairly obvious. If I remember correctly, the diode is reverse biased in normal operation, and there is a fuse in series with +. When things are connected backwords, the diode is forward biased and conducts large currents and thus the fuse blows....but I could be thinking of something else. Best to have someone check it...or post some really good close up pictures of the input half of the supply.

Did you do a voltage check on your car where your power supply plugs in to see if you only blew one fuse?

How did you check to see if the fuse in the PSU was good?

As the Diode is preventing reverse current, sometimes it gives its own life...like a fuse, have you checked the diode (I have seen on in a radio, don't know if it is the PSU)

sadly, im an idiot and have no idea what a diode is. The fuse is not blown though, there was some kind of black rubber over it, and i cut it off, and examined the fuse, which is fine.

Are you sure that tyyhe power supply doesn't work??
it could have just been the fuse that blew in the car, and the spark you saw was because you were shorting out the car battery, and the fuse blew..
Either that, or, no, there is no or, there couldn't be anything wrong with the power supply, because the fuse would have blown too quickly for any real dammage to occur...
I first though that you might hae blown up a capacitor by connecting the voltage around the wrong way, but I think you would have known about it, I did this a few weeks ago, and it went off like a gun..

The fuse can be blown and still look fine to the eye. You need to test it with a meter.