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Replacement AC adaptor with much higher current

  1. Apr 14, 2010 #1


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    Is it bad to replace a regulated AC adaptor that has an output rating of 9V DC and 200mA with a regulated AC adaptor of the same polarity that has an output rating of 9V DC and 1.7A? I know it's OK for the current rating to be higher than needed, but in this case the current rating on the new adaptor is more than eight times greater than that on the old one. Also, I think the equipment it would be used on only draws 75mA of that anyway.

    Would making this replacement have any adverse effect on the equipment the adaptor would power?

    The reason I ask is that I read on some site that you shouldn't use an adaptor with a current rating that is a whole lot larger than the one you are replacing, but it occurs to me now that maybe they were only talking about unregulated adaptors (where I can see it would be a problem because the output voltage would be too high). Do you think this might be right?
  2. jcsd
  3. Apr 14, 2010 #2


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    Staff: Mentor

    It should work fine. The only disadvantage is cost.
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