Need electical hookup advice please

[GeeMac]

I have an old power supply(wallwart) for a printer. It puts out 30 volts and 400 milliamps.  My charger is a sunforce 12 volt 30 amp model.

Link to the charger http://sunforceproducts.com/english/details.asp?id=74

If I hook up the 30 volts to the input side will it blow the charger which puts out only 12 volts?

Thanks

[ghurd]

The sunforce will blow up.

It will have the same issues as a windmill on a series solar controller.

The manual states max input of 25V.

A standard wall wart will be well over its rated voltage with a small or no load.

My cordless phone wall wart is rated 9V, but puts out 17V open circuit, so nearly double the wall warts rated voltage.

If the printer's wall wart runs the same, it is 57V open.

Even if it is a fancy, regulated wall wart, when the controller decides the battery is full, then the controller will see 30V. Or 20% over the max voltage.

Pretty good chance the 30V wall wart will burn up too.  It will not like being run at 12V.

Shouldn't be too hard to find a 12VAC transformer around 1/2A, add a bridge rectifier.  That would be better.  I still wouldn't run it through a solar controller.

May not need a controller if the battery is large.  I'm guessing the battery is not small if you bought a 30A controller.

G-

[GeeMac]

Thank you, young fellow. You have saved my a few bucks. )

Keep having fun

[kurt]

i would just use an lm317 iirc from radio shack there should be a drawing how to build the circuit for it on the back of the package if you have a radio shack that still has there parts bins they will have everything you need..... if not then you will have to order online.......  just be sure to get a 10 turn pot or you will not be able to fine tune the voltage you want......