Entering The SCARY WORLD of INVERTERS...

[High Cotton]

OK, I think I saw this wheel at THE BELLAGIO when I was in VEGAS!.......(this is a beautiful illustration provided in the "electrical study hall")
That's how much I understand POWER!
I did a "search" but couldn't come up with the answer..........

Can I install an INVERTER that will energize my 110V electrical outlets throughout the boat? (OK, now tell me that's how it's supposed to work!)

I have a KUBOTA 7.5KW generator, but I want to be able to plug in things like a flatscreen TV, or a "refreshment" blender without running the generator, or even my new "tanning booth"!

My brother suggested installing it in the cabin and just plugging into it, which sounds like something sailors would do in L.A. (Lower Alabama) ....(I mean NO offense to my Alabama friends, we DO share a state border...
OR to any of you in the forum that use that particular method) ......................

So can somebody give me a quick synopsys..... sinopsis....senopsys......
"low down" on INVERTERS?

Oh, and talk to me like I'm a 3rd grader......... "comprehension" was never a strong suit (even when I WAS in the 3rd grade!) .
Thanks!

[Latitude9.5]

There's several ways to do it, but yes with a decent inverter you can wire your outlets. I set my inverter up with a primary panel and a sub-panel. On the primary panel i have everything I can't or don't want to run off the inverter. Then I have a 30 amp breaker going to the inverter and coming from the inverter I have a subpanel, which runs all my outlets. When I plug in, the inverter goes to charge mode and passes the shore power through to the subpanel, when i shut the main down, the inverter instantly takes over and powers the outlets off the battery (inverting).

If you go with a small inverter, it isn't going to be feasible to wire it into the outlets, they usually have 3prong plugs, it would be easier just to do as your brother suggested. It's cheaper, but they put out less amps/watts and don't charge. (some put out some pretty dirty power too)

[High Cotton]

I DO want to go with a larger quality inverter for that reason, powering things while anchored out and no generator.
A sub panel sounds like a great idea!

[Pblais]

To do this you will need a charger for the batteries that can handle the input from either the generator or shore power (heavy duty switch), then you need the AC power to run from either the shore power or the inverter or the genset (another heavy duty switch). These are the expensive switches as they can handle LOTS of power.

The Inverter takes DC power from the batteries and makes AC power. If you wanted to run an AC appliance that uses say 3 amps at 120 volts the Inverter is going to need 30 amps at 12 volts to make the conversion (plus a little bit wasted). They both are equal to 360 watts. (Amps times Volts equals Watts A * V = W). That is most of what the chart has that matters here just now.

You can see when using 12 volts to run AC appliances you need 10 times the amps to make the same watts. A 120 volt 1000 watt microwave oven is going to eat the battery bank up pretty fast. The 12 volt DC batteries will need to put out 83.3 amps to run the oven. A couple hours on my boat at that load the batteries are dead.

That is the lowest down we get with Inverters. If you think about watts then the AC/DC stuff can be compared in a way you can deal with the numbers.

[GordMay]

Inverter FAQs:
Inverter FAQ - DonRowe.com - Frequently Asked Questions about Power Inverters

[High Cotton]

This is from the "Frequently Axe'd Questions"........

The inverter draws its power from a 12 Volt battery (preferably deep-cycle), or several batteries wired in parallel. The battery will need to be recharged as the power is drawn out of it by the inverter. The battery can be recharged by running the automobile motor, or a gas generator, solar panels, or wind. "Or you can use a battery charger plugged into an AC outlet to recharge the battery."

Can somebody 'splain that last stateMENT?!?
Can you plug a battery charger INTO the A/C outlet (being run by the INVERTER) and connect it to the batteries to charge ?????

I'm NOT sure I'm falling for that one!

[Rick]

You are correct. You cannot charge the battery using an inverter to power the charger...that would violate the 2nd law of physics. Regardless, what you probably need is an inverter/charger combination unit that has an automatic internal ac transfer switch. With an internal 30A or 50A transfer switch you can seamlessly use your shore power, generator or inverter (powered from the battery) to have ac to your ship's outlets all of the time.

The thing to be careful with this installation, though, is to understand that you might not want to power an electric hot water heater when in the inverter mode. That necessitates wiring the hot water heater (or similar non-inverter type loads) only to the inverter/charger ac input only and not the inverter output. (more on this later if you need)

The next thing to be aware of is that small gensets may be loaded more than one might think if the charger function is not a "unity power factor" load. Most "switch-mode" chargers are unity power factor corrected and, therefore, will not distort the genset output. Check out Magnum Energy sine-wave inverter/chargers or Outback Power or Mastervolt for such units.

[Randyonr3]

I'm one (like your brother) that does not like to conect systems together.. I have a Xantrex mounted under the nav-station about 6 inches from the batteries.. I've got a short lead that plugs into the inverter and the 110 wall plug..
MAKE NOTE, that all inverters are not created equel.. inverters take a certain amount to power to drive them, and some on the market would take the same amount of power weather they were providing 20 amps or 100 amps of power..
Xantrex is one inverter that only draws the power that is required to provide the amps being used at the time... If your using 3 amps to power a TV or DVD, your Xantrax will only draw what is needed (maybe a little extra) to provide the 3 amps.

[scotte]

+1 what Rick said. I've got a Freedom 30 charger/inverter. The shore power A/C is routed through it such that all 110VAC outlets onboard are powered by the inverter when it's powered up and there's no shore power.

[Alan Wheeler]

take the same amount of power weather they were providing 20 amps or 100 amps of power..

Hmmm maybe just a slight exageration. You are certainly correct that they are not all created equal. I think what you are trying to say is as I will explain.
The most noticable area's of poor vs good design are efficiency and waveform. Efficiency is the ability to take the minimum input and produce the maximum amount of output without wasting to much of the difference in heat. The other is the cleanliness of the output wave form. Cheap or poor quality designs will tend to have very poor waveform and the more expensive designs have a better output waveform. With the most expensive units producing pure sinewave.

[Latitude9.5]

Yea I noticed I had a buzz in some of my appliances with my old one, with the pure sinewave that went away, it also draws less amperage for the same appliance then the old one did.

Anyhow if you didn't get the link i posted (it got deleted) I can PM it to you, it's just a place you can download the install manual and see how things work, will give you an idea of what kind of wiring project you have ahead of you. I think if it would clear up a lot of confusion, that's why I posted it, not as endorsement for the product (although I am very happy with it).

[High Cotton]

PM me with that if you can, I appreciate that!

One reason I think I want an INVERTER is because the "free-standing" ice maker that I purchased at COSTCO (EXCELLANT unit, by the way!) will not produce ice running off the generator.
It works fine at my house, and works while on a tugboat (my brother's a tugboat Captain).......... so I assume I need to check the generator for 60HZ?

[colemj]

Originally Posted by Randyonr3

MAKE NOTE, that all inverters are not created equel.. inverters take a certain amount to power to drive them, and some on the market would take the same amount of power weather they were providing 20 amps or 100 amps of power..
Xantrex is one inverter that only draws the power that is required to provide the amps being used at the time... If your using 3 amps to power a TV or DVD, your Xantrax will only draw what is needed (maybe a little extra) to provide the 3 amps.

I think you really mean the no-load power consumption and you are correct that this should be a consideration based on how one uses the inverter. Some inverters draw a lot of power to simply operate without a load while others do not (no-load consumption). I have experience with three larger inverters:

Trace U2512 2500W = 0.3A no-load draw
Prosine 3.0 3000W = 7A(!!!) no-load draw
Outback VFX2812 2800W = 1.7A no-load draw

So there can be quite a difference between them. If one wished to just turn it when running a welder, a 7A no-load draw is inconsequential. If you wanted to run a couple low-draw lights or a LCD TV or charge a computer for a whole evening, that 7A is going to be higher than your loads.

Two empirical observation from those inverters above are that sine wave inverters draw more than non-sine wave, and that high frequency inverters draw more than line frequency ones. This is just a hypothesis from admittedly sparse data, so maybe someone else could throw theory behind it.

The other factor is the efficiency in which an inverter uses the DC power supplied to form AC. Again, my empirical observation from a limited data set leads me to think that sine wave inverters are less efficient than non-sine wave, but that the actual differences are pretty small and not worth worrying about.

Mark

[colemj]

I forgot to add that Xantrex makes a lot of differently branded inverters. They own Trace and Prosine, for example.

Also, to make my previous post clearer:
Trace U2512 = line frequency, non-sine wave
Prosine 3.0 = high frequency, sine wave
Outback VFX2812 = line frequency, sine wave

Mark

[Latitude9.5]

I'm not sure if this is "advertising" by the rules or not, I won't post a link , but anyhow here goes.

A guy here at the marina went with a true sine wave xantrax, had a lot of problems with and was told by tech support at xantrax "that's what you get from buying from a warehouse store" (west marine), basically they wanted to charge him for a firmware update on a brand new unit, so he took it back, got the Magnum Energy pure sine wave inverter charger.

I went with the exact same setup as him, magnum with remote panel and am extremely happy with it, the charger is extremely efficient and so far everything i have tried to run off of it has ran great. It doesn't draw anything at idle btw.

I do have an Outback MX-60 for my solar array and have been very happy with it's performance as well, but i have no experience with their inverters.