Mounting 600 Watt Inverter

[Pat Anderson]

OK, I got a new 600 watt marine inverter, really just a little guy, at the Seattle Boat Show, and Patty has been bugging me to get it installed. Ideally, it should be as close to the battery as possible, but I really do not see any good place to mount it back there.

So I am thinking about mounting it under the galley and running #10 wires from the battery to the inverter, a distance of what, 15 feet?. Now, I know Dr. Bob would find a way to mount it by the battery or run #4 cables forward but I don't have any really big cable.

Am I going to be OK doing this or do I need to go back to the drawing board on this one?

[Grumpy]

Pat,

Those wires are going to be taking about 50Amps. That will ruin your efficiency and could ruin your day by local (as opposed to global) warming.

Strongly recommend you sell me the brewery in exchange for some bigger wire.

Look up the tables in the WM catalog for 30 ft round trip and 50 amps

M

[Kelly Lynn]

I have a few pics of my inverter/battery charger. I believe I used #4 or #6 wire that is what the manufacturer calls for. It's a Xantrex 1000 Watt continuous. Just click on the boat name and check out the pics. I have had no problems and it runs great.

[Pat Anderson]

OK, won't use the #10 wires then, #6 probably. Is the distance a problem? I just really cannot see where this puppy could go close to the batteries (the supplied DC cables are about 3 feet long). That would of course be the best solution.

[lloyds]

Grumpy, are those 50 amps you mentioned for when you are running the inverter at its' maximum rated output? 600 watts seems like an in between range to me. Too small to run anything of substance but overkill for cell phone charging or computer charging. But, I am not an electrician so willing to learn here. And the lessons to be learned on this site are certainly priced right.

[Grumpy]

The 50 Amps refer to full rated 600W.

I agree that 600W is a bit low for many things but it will run an electric toothbrush, charge your I-pad, and a few other toys that shouldn't take anything like 600W.

The other consideration is just how much battery capacity you burn up with these things. ie. If you had a 50Ahr house battery you could run the inverter at full power for 30 minutes before reaching the recommended discharge limit.

I can understand that Pat probably wants quiet power for hanging out on the hook, but would be tempted to do what I have seen in an RV park and that is to put a Honda Generator in a cleverly baffled box which makes it very close to silent. The you can play with your toys for many hours on one gallon of gas.

M

[Sea Wolf]

Pat-

Do you have a windlass, and if so, do you already have some big cable running from the batteries forward to the back of the helm to the relays, and then forward to the windlass itself?

I do, and simply wired the inverter in parallel to the windlass wiring.

Just connect the inverter leads to the + and - windlass power supply wires at the relay, then just remember not to run the windlass and the inverter at the same time.

You will , of course, have a fuse in the inverter part of the circuit.

Joe.

[Kelly Lynn]

Your cables would go to your battery switch if you have two batteries. Distance and the gauge of the wire does have some relevance.

[Grumpy]

Excellent idea Joe. That could save a lot of time and money. (I still have bad dreams about the DC wiring and fuse costs for my 2KW inverter and that is only 3 ft away from the batteries)

Also good reminder about fuses. You can do a lot of welding with large wires and 12Vdc.

M

[Aurelia]

Pat, What kind of inverter did you buy, is it a water resistant/proof marine model and could live back there with the batteries in such a moist environment anyway? Do you have raised battery trays in the stern like I do? What are the dimensions of the inverter? I cheated and put a 1500watt model on the hull wall behind the water heater but I also have batteries up there as well and used #2 wire.

[thataway]

Lots of good information here. If you are about 15 feet to the closet, whiich is a decent place to put this inverter, then #4 wire for 3% voltage drop, and #8 for 10% voltage drop--go with the #4.

The windlass wiring is also a good suggestion. It also draws about 50 amps (and may be slightly undersized for the length of the run).

We have a 1000+ watt marine inverter, which is right next to two AGM group 31 batteries we added (both in the 25 and 255) in the back of the Closet and under the aft dinette seat. We have a 100 amp breaker there, and then charge the batteries thru their dedicated charger, or via a VSR from one of the two engines on the 255.

Agree, that there is not a lot of stuff you can run off a 600 watt inverter. For example we did run a smoker on the Cal 46 off a 300 watt inverter--and used the same inverter for battery charging. The 2500 watt inverter and 130 amp charger ran compressor refigration etc--but with 6 golf cart batteries.

[Pat Anderson]

The inverter is mounted now, about two feet from the house batteries, which are two 100AH Napa deep cycle marine batteries (wet cell) in parallel. I will use the large 12 volt cables supplied with the inverter, which are very short and very thick, don't really know the gauge. It is mounted on the underside of the splash well on the port side. I will run the 110 volts circuit forward attached to the bundle on the top inside of the starboard gunwale, behind the head, and locate the outlet box in the galley.

I doubt that I will ever run anything that would challenge our house batteries. The main 120 volt appliance is our coffee grinder. I am sure we will find a few other things. When I need to run the toaster oven, I will fire up the Honda 2000i!

[seabeagle]

I have a 500 watt in mine with 10 gauge about 3 feet from the battery. 10 is what it came with.