Duncanwood wrote:
On Mon, 15 May 2006 18:27:43 +0100, The Natural Philosopher wrote:

aussie bongo wrote:
"Lobster" wrote in message
...
I'm thinking of buying an 12V - 240V for the car, to enable me to
charge/run devices such as a laptop / mobile phone(s) / AA batteries
for gameboys & camera etc etc while on the road (one at a time!);
they seem to be as cheap as chips these days and this would enable
me to use the standard mains chargers for all the above devices
rather than buying separate low voltage kit to connect each of them
up to the cigar lighter.

Sounds good in theory, but are there any gotchas? Eg, safety? Does
it run a car battery down more to power up a laptop via a 240V
inverter than directly to the cigar lighter? etc etc

Can't help feeling an inverter would be much better if wired or
plugged into the car some other way than via the god-awful universal
cigar-lighter plug...

Thanks
David
i dont know about power usage on a laptop, but,
i do know that 100w drawn from an inverter at 240v, will give you
less than 1/2hours usage.

Car bateries are 40-70Ah, and at a nominal 12v, that is 480-840Wh.

Giving and expected uptime at npominal 80% eficiency of say 4-8hrs
roughly.

one thing to remember if you get one, is that you have to make sure
it is turned off with no power going into it whilst starting the car
as to do so will damege the inverter.

Total ******** as well.



You're failing to take into account quite how badly designed most
"cheap" invereters are, they're realy easy to break. Might would have
been better than will though.

Mmm.

One upon a time, I took a trip in a plane...and being of that bent,
inquired as to what the whining was that I could hear as the pilot
prepared to take off "its the rotary converters spinning up: They supply
all the various voltages we need for the equipment". (it was a plane
decdicated to radar testing and full of equipment racks) I nodded sagely
and said 'surely it would be lighter to put in solid state inverters'...
"Mmm..." the pilot said "Until you watch what happens to the battery
voltage when we pull the undercarriage up and roll the flaps back in"

The inertia of the rotary converters acted like a ****ing great
capacitor apparently...