|
|
|
|
Inverter Size
On 30 Dec 2003 10:32:28 -0800, (Dan) wrote:
Whether in a truck or a boat, it's inefficient to convert DC to AC
back to DC. You'd be better off powering a tower or laptop computer
directly from the DC off the vehicle. A trip to Radio Shack should
provide all the parts needed. An AT power supply for a tower computer
has +12V, -12V, +5V, -5V, and ground. For the +12V and -12V, you will
need to filter and regulate the DC feed from your battery bank. The
+5V and -5V can be derived from your filtered 12V side, just step the
voltage down....
Dan Schiro
Though it sounds paradoxical, using an ordinary regulator to derive
5 volts from a 12 volt source is normally less than 5/12 efficient or
42% and its the +5 volts output that takes most of the current, if
I recall. (using a resistive voltage divider is even more wasteful
still.....) I'm not convinced you would show a power savings, with
the homebrew DC source approach over a 12/120AC inverter.
There is a way to convert DC sources efficiently though, by using a
buck switching converter. They can show efficiencies in the 90s, but
they cost.....
I liked the packaged DC supply for PCs approach that someone
mentioned. That would be a usable alternative to an inverter, IMO.
Brian Whatcott Altus OK
|