From: sukitoby@...
Subject: Re: inverter suggestions for EVC
My question: Has anyone installed an INVERTER so that you have 110
VAC while traveling and parked. There is plenty room in the battery
area.
I've used a small 200 watt inverter that plugs into the cigarette
lighter outlet. It powers a laptop computer while charging the
laptop's battery, and I also use it to charge AA batteries via a small
charger. I normally try and run the inverter only while the engine is
running, to save draw on the coach battery.
Suggested watts (300, 500, 1000 ??) Suggested Manufacturers?
Wattage ratings depend on what you want to power with the inverter.
Can it be wired to work with the existing 110 V wiring and outlets
already in the EVC.
That would be a significant job. The existing 110 V wiring is
permanently hooked to the magnatek converter. You'd have the inverter
trying to power the converter, which would try to power the inverter,
which would power the converter, etc. Sounds like a great perpetual
motion machine at first, but the laws of thermodynamics prevent that
setup from doing anything except generating lots of waste heat while
it drains the battery, at best.
You'd need a mechanism to prevent having both the inverter and the
converter connected simultaneously. You'd also need an absolutely
failsafe mechanism to prevent connecting the inverter's output and the
shorepower input simultaneously. If two unsynchronized 110VAC sources
ever compete to power the same outlet, something's going to explode.
I think it would be less trouble just to install new AC outlets, or
else rewire one (or both) of the outlets to be connected to the
inverter ONLY, and not connected to shore power.
If you DO install a high wattage inverter, put it as close to the
battery as possible. It's much more efficient to make your long cable
run with 110V instead of 12V, and keep the 12V cable as short as
possible.
Please help - by the way Sharp has just release a miniature
Microwave called The Half Pint which would be way cool for your EVC
and it has a low wattage demand.
Low wattage means it doesn't heat terribly fast, since the microwave
wattage is directly related to the amount of heat it puts into the
food in a given time. To heat a given amount of food/water to a given
temp, you end up using close to the same amount of energy out of the
battery, whether it's a high wattage draw for a short time, or a low
wattage draw for a long time.
Personally, I'm not a big fan of microwaves for use in RV's, unless
you're camped at a campground with electric hookups. I know some
folks like 'em, though. It just doesn't seem like a very efficient
way to heat food, burning petroleum to push a piston to turn a
crankshaft to spin an alternator to generate DC to charge a battery to
power an inverter to generate AC to power a microwave tube to heat
water. Far less trouble to place the object to be heated directly on
top of the burning petroleum, via a propane stove. Batteries are
terribly inefficient energy storage devices when you compare them
against propane tanks. And with the limited storage space in the
EuroVan, allocating space to a microwave plus an inverter big enough
to power it, and perhaps an additional battery to power the inverter,
just isn't a worthwhile tradeoff for me.
--Rich (the curmudgeon)
