"Robert Fenster" wrote in message
news:rC9wf.4036$Dh.2062@dukeread04...
I am interested in getting a 100W - 150W power inverter for the car.

I figured rather than buy every single ligher adapter for every cell
phone/laptop/digital camera, the power inverter would do the trick.

My concern is based on the fact that both cars i have are small 4 cyln
engines.

Assuming i remove the lighter adapter if while i drive throught the
mountains of West Virigina (once a year), what are the pro's and con's of
such a solution.

(NOTE: I do see the irony of plugging a transformer into an inverter, but
it
seems like a workable solution).


Thanks in Advance,

Robert Fenster



A word of caution with cheap inverters, they deliver a square wave that has
the same RMS as a 120V outlet, but not always the same peak. They are fine
for heating but may give problem with rectifiers like battery chargers.

I would measure and compare the charging current to make sure is roughly
the same with inverter or 120V house current. Need to measure the current
because the voltage is determined by the battery and is fairly independent
of the current.

As far as the 4 cylinders, I would not worry. A 150W inverter is more than
adequate for charging and it will only take what it needs from the battery.

A phone charger may use 2W and the inverter efficiency at such low load may
be only 10% so you may have a 20W drain on the battery, that is less than
one head light. You can measure the No Load current to the inverter and
expect that to be a baseline, small loads will add little to it a full 150W
may add 15Amps at 12V.
Running the inverter at full load is probably more taxing for the inverter
for the battery and the engine, even uphill.
The figures above are only ball park not knowing the specifics.

If you can find a 20W sine wave inverter than all concerns disappear.

Mauro