Powering laptop etc in car from inverter?
"Slurp" wrote in message
...
"Ian Stirling" wrote in message
...
In uk.rec.cars.maintenance Slurp wrote:
"aussie bongo" wrote in message
...
snip myu comment
but is that 40w &15w at 240v or the normally 18v that most laptops
use??
this makes a big differance
40W is 40W whether its at 1nV or 306MV
P(WATTS) = VOLTS x AMPS
40W from an 12V battery = 3.3A
40W from 240V rms supply = 0.167A rms
Average car battery = 35Ah, assuming 100% conversion efficiency = 10hrs
Err, no.
If it's measured at 240V, you've then got to addin the efficiency of the
inverter.
Err, no
you have to add in the INefficiency, ie if 80% efficient then add in 20%
If it's measured at 12V, you don't.
????? The extra current due to the inefficiency of the conversion has to
be supplied from 12V!!!!
That's just what Ian said.
--
Malc
"When I say 'Run like ufck and commit assault on a police officer
several times,' run like ufck and commit assault on a police
officer several times."
- Channon
Transmetropolitan
|