I need advice on Inverter Purchase

[Mahatnmacoat]

I hope Grumpy or Craigavon or Pconroy or JimD get a look at this question. I want to hook up a one thound watt inverter to power the two outlets in the kitchen, one is the galley GFI the other is the microwave. The power stream is either shore power or genset to auto transfer switch, from transfer switch to service panel. From service panel 30 amp main to 15 circuits. Two 15 amp circuits to the galley. The inverter is a pretty good one, Xantrex. Two 15 amp three prong outlets on the output end.

The transfer switch and the service panel are close to each other and right over the house battery bank. I'd like to switch the 30 amp main OFF, the inverter ON, make my coffee cook, up my oatmeal and read the paper. It would be nice to have a failsafe switching setup so there's no chance of turning the main and the inverter on at the same time but I trust myself to make sure it's either or.

I'm sure I'll get some good back feed and thanks in advance.

[pconroy]

Help me out with a poor memory - what's your coach now? Do you already have an inverter? Are you upgrading, replacing or saying you'll keep the one you have.


You just want to add some circuits?

[Mahatnmacoat]

Thanks for the prompt response!
2002 Designer 3230
Xantrex 1000 watt inverter. The inverter has two female three prong outlets.
Don't want to add circuits, want to link the inverter to two specific existing circuits, the galley and the microwave outlets.

One way to do it would be to piggy back lines from the two breakers through an off/on switch to the inverter. Click the 30 amp main off, click the inverter on. Reverse order when I want to use shore power or the genset. However neatly I might do the work that approach seems kind of jury rigged to me.

What say ye?

[ALJO]

I use 2 designated circuits (microwave and fridge) with 3 way switches. So it is either on the inverter or shore-power.

[Mahatnmacoat]

Thanks ALJO, can you say more about the three way switch and how it's wired?

[Grumpy]

I think connecting the two different circuits is the challenge.

I would only do the micro and drop an additional outlet down from that receptacle using wire mold. That way you could go from the breaker into the inverter and out to the micro provided you buy an inverter that has a build in transfer switch and have room to put it close to the breaker panel. Since that size inverter will only let you run the coffee pot or micro and not both at the same time anyway. No need for any additional switches, it will all be automatic whether on shore of geny.

That is what I did in our 08 SENECA and that way we could run a crock-pot while driving since it would ride in the sink.. Had dinner almost ready when we arrived. Of course the inverter was already wired to the micro circuit.

[craigav]

Hi Mahatnmacoat,

I would use a transfer switch like this one.
https://www.amazon.com/Xantrex-80809.../dp/B004S5Y158 and just feed one circuit.

Also, I am concerned that you don't have a strong enough inverter, while 1 thousand watts seems like plenty enough and perhaps your microwave says on the front 8 or 900Watts, they actually use more than that, those watts are for the microwave energy usage. For example take a look at this https://www.amazon.com/Microwave-Cub...1JlZGlyZWN0JmR Even though this says 900 watts energy use if you read down through the page to the middle under "Details" you will find that is says 900W (Output) 1350W (Input) which is typical of all microwave ovens to consume more watts input than they output. A 1 thousand watt inverter would not be powerful enough for this microwave.

With all this in mind, I would suggest checking your microwave as I suspect your inverter will not be powerful enough for it. Let me know what you find out and I can give you more thoughts about what may work better for you.

Thanks, Craig

[cpd1343]

I use this:

https://www.amazon.com/gp/product/B0...KIKX0DER&psc=1

[Mahatnmacoat]

When I ask for expert advice I usely profit from taking that advice. Parenthedly, I was a licensed master and marine sureyor for over thirty years. When asked for my expert advice I charged in six minute intervals, a tenth of an hour. I learned that billing protocol from lawyers and accountants.

My microwave is 1.5 kw in, the coffee maker is 1.3 kw in. Well, I always needed a bigger boat. Now I see I need a bigger inverter. Since I'm in good health it looks like as I get older my problems are getting better.

Thanks to all you guys for your generous help. I have enough information to safely hook up the right inverter.

Best regards

[pconroy]

Originally Posted by Mahatnmacoat

I learned that billing protocol from lawyers and accountants.

As a former tech consultant, I learned early that:




If you cannot be part of the solution,

Then there's good money in perpetuating the problem!

[Mahatnmacoat]

Ha! I've been on the wrong end of that business administration principle. That lecture opens with, there's no such thing as a lie of omission. As a marriage was circling the drain my second ex-wife said, "You're to honest for your own good."

[craigav]

As a thought, if you are looking at a larger inverter, consider one that has a charger and a transfer switch built in. For example, I have tested in my shop but yet to install it is a green Aims 2500 watt inverter that has a built-in transfer switch. My plan is to feed the input of it the power line going to the breaker panel, and the output going into where the breaker panel main input is located. That way all plugs will be hot when on inverter power or shore, or generator power and I can choose what to turn on and off just like if the generator or shore power was available.

I also mentioned the charge circuit, because it has a charge circuit all you have to do is unplug the current converter\charger. If you choose another brand (many good ones out there and likely better than AIMS) then you may need to consider a way to power off the charger\converter as you wouldn't want that to be on while using the inverter.

Just a thought to share, as this is my plan.

~CA

[Jagiven]

Originally Posted by Grumpy

I think connecting the two different circuits is the challenge.

I would only do the micro and drop an additional outlet down from that receptacle using wire mold. That way you could go from the breaker into the inverter and out to the micro provided you buy an inverter that has a build in transfer switch and have room to put it close to the breaker panel. Since that size inverter will only let you run the coffee pot or micro and not both at the same time anyway. No need for any additional switches, it will all be automatic whether on shore of geny.

X2, depending on your layout adding an outlet under the microwave, above the kitchen upper cabinet is fairly easy to do.

My biggest concern is the 1000W inverter. Have you confirmed the microwave power consumption? I bet it is north of 1200W, and maybe as much as 1800W.

[JimD]

Originally Posted by Grumpy

That is what I did in our 08 SENECA and that way we could run a crock-pot while driving since it would ride in the sink.. Had dinner almost ready when we arrived. Of course the inverter was already wired to the micro circuit.

A crock pot while driving. Hmmm, the only big problem is the wonderful smell coming from it making you want to pull over and eat. Would that be considered distracted driving?

[JimD]

You basically could do anything you want. If needed, you could have the inverter power all outlets instead of just certain ones that are on different breakers. If the outlets are on the same breaker, that mod would be easy.

The trick is the isolation so the shore/generator/inverter are all isolated from each other. Ignoring the transfer switch that already would exist for shore power and generator, you would need a "switch" for the inverter/other 120 volt feed.

This "switch" can be a standard automatic transfer switch or just a manual one you throw when the inverter is needed. This manual switch would just need to be a double throw version meaning a common connector that connects to one or the other connectors. Flip the switch one way and the inverter is connected. Switch it the other way and the 120 volts from shore/generator is fed through. The switch would need to be heavy duty enough to match the current of everything.

Instead of the switch you could use a heavy duty relay controlled by a much smaller switch. The relay would then do the actual heavy duty switching.

If the outlets are on the same breaker you would disconnect the input to that breaker and connect it to the one of the 2 "output" connectors on the switch or relay. Then wire the inverter output to the other terminal. Then connect a wire from the common terminal on the switch/relay back to the breaker.

Hope this makes sense. A transfer switch would be the most expensive option but the easiest one for operation.

Keep in mind that modifying anything in the 120 volt system could be potentially dangerous. If anyone got injured by the modification you could be held legally liable.

[Bakedalaskan]

Craigav, your theory is correct but you will only be able to use 2500 watts of power before the inverter trips out when on shore power. I did what you suggest with a 2000 Aims inverter/charger. Nice tidy install inside an unused space under the microwave. During the first outing while on shore power the whole works goes dead. What is going on here? Take half the camper apart to find the Aims breaker tripped. Reset it and 10 minutes later tripped again. I am on shore power and cant run a coffee pot and toaster? Sure enough, exceed 2000 watts and the inverter trips right out. The solution was to install a transfer switch and turn off the Aims charge function. I either have shore power or inverter power and have to trip the breaker for the converter while on inverter. I wanted the inverter for simple things like making coffee, heating soup, watching tv quietly without needing the generator. The inverter does all these things with ease but when you say the inverter will pass through shore power I expect 3600 watts to bass through. Which is 30 amp service. The circuitry to do this would be a minimal addition to the inverter and would make it a much more useful investment. Knowing this; I would have just bought a 2000 watt inverter without the charge function and saved a bunch of money on my car insurance.

[Vicr]

This is all very interesting but the foundation to inverter power is a DC power source, Batteries, that's where the base engineering needs to start. The amount of ah to supply end user X with X amount of watts for X amount of time.

[ALJO]

My 3000 watt inverter has 2 outlets (different circuits) and run 2 lines to the power panel where I make the split through the 3 way switches (regular wall switches) P-Contact of each switch goes to the fridge and microwave the other contacts go to the converter and designated breaker. During travel Fridge is on inverter. Microwave I only use when needed.

[craigav]

Originally Posted by Bakedalaskan

Craigav, your theory is correct but you will only be able to use 2500 watts of power before the inverter trips out when on shore power. I did what you suggest with a 2000 Aims inverter/charger. Nice tidy install inside an unused space under the microwave. During the first outing while on shore power the whole works goes dead. What is going on here? Take half the camper apart to find the Aims breaker tripped. Reset it and 10 minutes later tripped again. I am on shore power and cant run a coffee pot and toaster? Sure enough, exceed 2000 watts and the inverter trips right out. The solution was to install a transfer switch and turn off the Aims charge function. I either have shore power or inverter power and have to trip the breaker for the converter while on inverter. I wanted the inverter for simple things like making coffee, heating soup, watching tv quietly without needing the generator. The inverter does all these things with ease but when you say the inverter will pass through shore power I expect 3600 watts to bass through. Which is 30 amp service. The circuitry to do this would be a minimal addition to the inverter and would make it a much more useful investment. Knowing this; I would have just bought a 2000 watt inverter without the charge function and saved a bunch of money on my car insurance.

Hi BakedAlaskan, (good name btw )

The Aims 2500 that I have has a 30 amp transfer switch built-in. When on shore power (or generator) it is rated to pass all 30 amps through it, when on inverter I am limited to the 2500 watts.

Which model Aims inverter do you have? Perhaps there is a difference between yours and mine, or possibly I have never exceeded 2500 watts. Thanks, Craig

I just checked the manual on mine, it says that the transfer switch "Bypass Breaker rating (120vac) is 30A" Although I didn't physcially look at the Inverter just now as it is not handy to check. Also, the manual says it can put out 7500 watts for 20 seconds. I suspect yours and mine is of a different model line ~CA

[Vicr]

Originally Posted by craigav

Hi BakedAlaskan, (good name btw )

The Aims 2500 that I have has a 30 amp transfer switch built-in. When on shore power (or generator) it is rated to pass all 30 amps through it, when on inverter I am limited to the 2500 watts.

Which model Aims inverter do you have? Perhaps there is a difference between yours and mine, or possibly I have never exceeded 2500 watts. Thanks, Craig

I just checked the manual on mine, it says that the transfer switch "Bypass Breaker rating (120vac) is 30A" Although I didn't physcially look at the Inverter just now as it is not handy to check. Also, the manual says it can put out 7500 watts for 20 seconds. I suspect yours and mine is of a different model line ~CA

A 2500watt inverter (any inverter) runs about 80% efficiency 2500 x .8= 2000 watts. 2000w/120v= 16.66 amps.