[massplumber2008]

Hi guys!

I have a 3500W/7500W (peak) inverter I want to install on my truck. With my specific requirements, I think there are two installation options:

1) Install the inverter 30 linear feet (in terms of running the wires) from the battery and run large cables from the inverter to the truck battery, or

2) Install a battery next to the inverter and run smaller wires between the new battery and the truck battery (30 feet away).

I am wondering what size wire for #1 option above (I am getting confused on 00 wire, 1/0 wire, etc.).

I am also wondering what size wire you would recommend for option # 2 above. Further, regarding option #2, would a deep cycle marine battery be best here?

I will be installing a 600 Amp. ANL inline fuse (on positive) and will be running basic power tools off the inverter.

Please advise...

Thank you.

Mark

[medic-dan]

30' is just too far. At 3500 watts you're drawing well over 300 amps when you account for loss.

Mount the inverter as close to the battery/alternator as you can.

Option #2 isn't that effective. The alternator will be trying to keep the battery charged. Worst case, you have a battery that's drawing a great MANY amps to recharge and an inverter that's also drawing a lot of power. If the truck is not running, if you don't "isolate" it from the truck you'll have two dead batteries.

Can the vehicle alternator handle the demand?

Here's option #3, stick a portable generator in the bed of the truck. It's self contained and you can run it for hours.

[hkstroud]

My thoughts for what they are worth.

I think the question is, or should be, how much power do you need. Second is what size alternator do you have or are willing to install on your truck.

A 200 amp alternator puts out 2400 watts at 12 volts. 2400 watts converted to 120 volts is 20 amps. Next question is how much does a 200 amp alternator put out at idle speed. Assuming your need if for motorized electric tools. AC electric motors need a sine wave current. The cheaper inverters put out a square wave signal. More expensive inverters put out a modified sine wave signal. Top of the line inverters put out a true sine wave signal. Expect a 20 per cent loss in power using a square wave signal to a AC electric motor.
Cable size is determined by amperage. A 30' cable capable for 200 amps at 12 volts is bigger than you would want to carry around. 20 amps at 120 volts would require #12 or possible #10 to minimize voltage drop.

[massplumber2008]

Just needing to run a drill or a sawzall on a very rare occasion is all... not planning on using it every day or for long periods... more for emergencies, really!

Thanks for your input guys!

Mark

[hkstroud]

Lithium cordless tools with extra batteries. Combined with a small, cheap inverter on your truck, so you can charge on the go, should give you the ultimate in convenience.

I seldom pick up a corded drill any more, except for my hammer drill. Don't have a cordless hammer drill but going to get one some day. I have an off brand cordless sawzall but not lithium. Good for short uses but batteries are always dead. That is nice thing about lithium batteries, charge is suppose last for a year.

[massplumber2008]

should give you the ultimate in convenience

That is exactly the idea, Harold!