[TenTec] TenTec Digest, Vol 51, Issue 8

[Dr. Gerald N. Johnson]

On Tue, 2007-03-06 at 19:01 -0500, Gary Hoffman wrote:
> Agreed, you could run everything on 12 volts.  That would work for many
> common situations.
> 
> It would not work for my setup with scanners and commercial radios and
> computers, and....well you get the idea.
> 
> 73 de Gary
> 
Hmm, the wall warts for my scanners put out 12 volts DC.

Laptops can be run from 12 volts with reasonably priced 12 to 18 volt
step up supplies.

Desktop computers could be run from 12 volts, though the current may not
be compatible with 18 gauge power cords. With th computer supply being a
switching supply, there is no fundamental reason it couldn't be designed
to run from 12 to 14 volts instead of 280 volts except that the switched
current has to be 20 times as large.

Individual 120 volt items may have to be run through an inverter, but if
the converter is customized to the load each supplies, the system
efficiency should be far better than running an assortment of part time
loads on a single inverter with the power to run the peak assortment of
loads. An inverter output section takes the same drive and control power
whether loaded or not and that's a significant part of its inefficiency.

-- 
73, Jerry, K0CQ,
All content copyright Dr. Gerald N. Johnson, electrical engineer