If you watch my video you will see when I short out the tracks no spark, no arching, no nothing other than the buzzer sounding. I have mine set to 12 amps due to the combo of passenger cars (since converted to LED) and EOB engines which draw lots of current at slow speeds, tends to trip the PSX are lower current settings. When I was using fuses, it would get arch welding all over the place. With the PSX no more.
Also remember you can get these in one, two, three, or four channel outputs.