1

I have an ~10-year-old hub (Surecom EtherPerfect 505ST if anyone's interested) that says "DC 7.5V" below its power connector. Unfortunately, I can't find the adapter, but I do find one that fits but outputs 12V. My question is: is a modern computer peripheral device that takes an adapter likely to be able to safely regulate down from 12Vdc to 7.5Vdc? Since it's an old bit of hardware I'm not terribly worried about losing it forever, but I have to weigh the risk of damaging it against the likelihood of success if I keep looking for the proper adapter.

(Or maybe I have found the proper adapter and the one that came w/the device supplies more than 7.5V)

PenguinLust
  • 135

1 Answers1

3

You should never use a significantly higher voltage rating adaptor on any kind of electrical device. If you do so you are risking damaging the equipment and anything else that you might have plugged into it.

You can, on the other hand, use a higher current rating without worrying about the device you are plugging it into. Devices only take as much current as they need.

Think of it like a pipe, with a vent at the end. The voltage is the force of the water in the pipe, the current is the thickness of the pipe. The vent will allow a particular trickle of pressure (voltage) to pass through. Too little pressure will not allow the vent to work, but too much pressure will blast the vent off and destroy it. The thickness of the pipe (current) is largely irrelevant to the pressure in the pipe, what is important is the amount of pressure that the contents are under.

An 8V adaptor might be okay, but it depends entirely on the electronics in the device you are powering. Given that a 7.5V adaptor is already pretty odd I would suspect it is asking for that voltage for a reason. 12V will almost certainly lead to an abruptly shortened life for what you are plugging it into.

Mokubai
  • 95,412