"Tony Sivori" wrote in message
news
I have a non mission critical device (a "Super Bark Free" ultra sonic
dog anti-bark trainer) that as an alternative to battery power calls for a
200mA 6V DC power converter.

I am wondering if I might get away with a higher powered converter. For
instance, I have an old PC speaker wall wart DC converter that is 300mA at
9 volts.

Will most low power devices like this tolerate a 50% over volt and over
amp, or would it likely result in a quick failure of the device?

--
Tony Sivori
Due to spam, I'm filtering all Google Groups posters.

The current rating of the power supply is unimportant - sort of - as long as
it is at least enough. I say "sort of", because it depends on whether or not
the supply is regulated. If it is, then it doesn't matter how little, or how
much, up to the rated current level, that you draw from it. The voltage will
remain at 9v give or take. If the supply is unregulated, then the chances
are that it will be rated at 9v nominal, only when it's loaded close to its
maximum. At lower currents, the voltage could well be 20% above that,
particularly with small transformers which are notorious for poor load
regulation. So the output could easily be up around 11v when lightly loaded.

Your bark trainer might well tolerate this, even though it represents
getting on for 100% over-voltage, but it is a risk that I don't think I
would want to take for the sake of shelling out the small amount that a
suitable 6v regulated wall wart would cost.

Arfa