power inverter installation

[Jay Darst]

Jeff,
I agree with the 20' of 4/0 cable.

Looking at the Ancor Marine Wire size chart...

If you had a round trip of 40' of 4/0 wire pulling an Inverter that is
supporting a 12.5amp load(1 roof A/C unit)you would experience a 1.8%
voltage drop.

So if your batteries with no load read 12.7 volts, the new load would
cause a voltage drop down to 12.5 volts due to wire resistance. By
comparison, if the round trip of 4/0 were to be only say 12', the 12.7
volts would be reduced to 12.6 volts.

Both of these examples will work just fine.

Put your inverter where its best for it and for you, keep the 4/0 down
to 50'. if your inverter is 92% efficient and is rated high enough to
pull a 25amp/110volt load, the resistance in the wire will cause a
4.8% reduction in voltage, or 12.7volts will be down to 12.1volts.

Of course how long the batterys can susatin this big load depends on
the battery bank.

If you wanna run the microwave, and it takes 15amps of 110volts, your
resistance in the 4/0 will cause a 2.9% reduction in voltage. Or 12.7
volts would be reduced to 12.3volts.

This is all based on having a sufficient supply of amps at 12.7volts
and that where ever the power is coming from, it can maintain
12.7volts.

Check out the wire chart I sent to the files called "Wire Size Chart",
it will help you figure out what size wire you need for your projects.
Keep in mind, the chart is for the bigger AWG wire sizes instead of
the SAE wire sizes.

Brother Dan has 40 or 50 feet of 4/0 powering his inverter, mounted in
the mid compartment on the pass side. He runs front a/c while cruising.

Werks grate with a 320 amp alternator supplying the juice ;~}

Jay Darst
85PT40
Springfield, IL where I use 4/0 for all battery connections except
from the alt to battery's which is 1/0. All werks grate!





--- In WanderlodgeForum@yahoogroups.com, "Jeff Miller"
wrote:
I have had very good service from
> mid-bay installation and about 20' of 4/0 cable. Mine was wired to
> run the rear A/C unit, and did so with minimal voltage drop.
> - Jeff Miller
> in Holland, MI
>