There are a number of practical problems with finding out. The machines have interlocks that won't let them run if they're open. Also, the electrospray only works to make fine droplets, dry them, and give them a charge in a vacuum, and you've broken the vacuum. Also, the port is very tiny and embedded in a skimmer cone, so your finger can't get close enough. I don't recall the voltage, something like 5-7 volts? But I don't know how many amps.