Possible Duplicate:
Choosing power supply, how to get the voltage and current ratings?

I have a device that I brought to Europe from America. It has a 110V AC/ 9V AC power adapter that stopped working. Over here I found a 220V AC/ 9V. I'd like to know if it'll work despite the 110V/220V difference since the device will receive the same 9V


marked as duplicate by Olin Lathrop, Dave Tweed, Leon Heller, Kortuk Oct 23 '12 at 13:49

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • \$\begingroup\$ You'll have to look at the current needs but assuming both are 9v DC yes. \$\endgroup\$ – kenny Oct 23 '12 at 11:41
  • \$\begingroup\$ both adapters are 9VAC. \$\endgroup\$ – hikizume Oct 23 '12 at 11:43
  • 1
    \$\begingroup\$ It doesn't matter how the power supply makes 9V, only that it does. The current rating also has to meet the minimum requirement. For more detail, see the question I linked to above. \$\endgroup\$ – Olin Lathrop Oct 23 '12 at 11:47

Your 9 V AC will be 9 V AC; the secondary side doesn't know about the primary voltage. So that's no problem.

What could be important is that in Europe you'll have 50 Hz output, whereas the US adapter will output 60 Hz. (Well, it doesn't make 60 Hz, that's what the mains supplies in the US.) This is not a problem if the device converts it to DC (most likely), but if you would use it for a digital clock that will run 17 % slow if it gets its clock from the mains frequency, and expects 60 Hz.


Not the answer you're looking for? Browse other questions tagged or ask your own question.