Inverter installation

Leigh Murtha

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We're installing an inverter in our Eagle 321RSTS and need a little guidance (ok, a lot). Our 3000w inverter has an auto transfer switch rated at 30 amps, but obviously, we have 50 amp service...I'd like to power most/all of the RV with it. I'm not sure where the "inverter prep" is located, or where to put the inverter to power the RV. sure, we 'can' just plug in to the inverter, but that's not really what we want. Can anyone help us with photos of your setup or diagrams?
 
In the beginning your battery capacity is key to when you say you want to power most/all with your inverter. If you have a stock setup, then you will probably not have enough battery capacity to power your rv without reservation. .

And next what is your plans about replenishing your battery or batteries, like certain amounts of solar. One of the reasons I ask is that you say Inverter prep. So it sounds like your setup is probably minimum at best with factory solar. With a solar prep if you have a solar, its probably one panel. But its also possible that you have a setup that lets you hook up an inverter to a couple of inside receptacles only , too.

What year is your rv?
 
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I would start by defining what you want your system to be capable of doing and how much you want to spend. An inverter system setup can range from $200 to $10,000 and higher depending on requirements.

The key is to only invest the money once. You want to avoid getting part way through your setup and figuring out you need to replace some of the components you have already installed/purchased.

An inverter opens up lots of camping options. We camped off grid at the Grand Canyon for a week last summer. Microwave, internet, TV, and other items throughout the day. Ran the generator for a few hours in the evening to cool down the RV and charge the batteries. All possible with an inverter, large lithium batteries, solar, and a high output battery charger.
 

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In the beginning your battery capacity is key to when you say you want to power most/all with your inverter. If you have a stock setup, then you will probably not have enough battery capacity to power your rv without reservation. .

And next what is your plans about replenishing your battery or batteries, like certain amounts of solar. One of the reasons I ask is that you say Inverter prep. So it sounds like your setup is probably minimum at best with factory solar. With a solar prep if you have a solar, its probably one panel. But its also possible that you have a setup that lets you hook up an inverter to a couple of inside receptacles only , too.

What year is your rv?
We have a 2024. 400w solar (added a 200w panel in parallel), 400ah Renogy Lithium Smart batteries. Slowly ticking away at all the upgrades :)
 
You can't power your entire rig from the inverter. As you have 50 amp service, there are two separate 120 volt feeds that would be powering different items in the rig. For example, if there are 2 AC units, one leg of the input would feed one AC and the other leg would feed the other AC. It would not be feasible to tie everything together with one inverter.
 
Good upgrade, You still may not be able to run mainly your ac. But I have a similar setup, 600 watts Renogy solar panels except for the Lithium batteries. I replaced the 12 volt wet cell batteries to 6 volt GC 2 golf cart batteries to a total of 232 ah. But while I have the 50 amp power panel and cord, I did rig mine with 2000 watt inverters, and wired my inverter directly into my power panel, since I did not have the auto transfer switch.


When I am plugged into 50 amp, I have a feature that disconnects my inverter manually. I actually added a spare backup inverter too, since I converted my 12 volt fridge to a residential 110 that fit right into my factory cabinet . Our 12 volt would never work properly. I will take pictures tomorrow of what the factory setup was, to my two receptacles in my foward locker. And this is exactly what Jayco said that I could only use in their setup as it rolled out of the factory.
 
I would start by defining what you want your system to be capable of doing and how much you want to spend. An inverter system setup can range from $200 to $10,000 and higher depending on requirements.

The key is to only invest the money once. You want to avoid getting part way through your setup and figuring out you need to replace some of the components you have already installed/purchased.

An inverter opens up lots of camping options. We camped off grid at the Grand Canyon for a week last summer. Microwave, internet, TV, and other items throughout the day. Ran the generator for a few hours in the evening to cool down the RV and charge the batteries. All possible with an inverter, large lithium batteries, solar, and a high output battery charger.
We'd like to be able to run what we can off of 30amp...ish. Like, I don't expect to be able to run our A/C, but we definitely need to run a CPAP overnight. maybe the TV for a bit. Charge some devices...
You can't power your entire rig from the inverter. As you have 50 amp service, there are two separate 120 volt feeds that would be powering different items in the rig. For example, if there are 2 AC units, one leg of the input would feed one AC and the other leg would feed the other AC. It would not be feasible to tie everything together with one inverter.
 
Good upgrade, You still may not be able to run mainly your ac. But I have a similar setup, except for the Lithium batteries. But while I have the 50 amp power panel and cord, I did rig my 2000 watt inverters, and wired my inverter directly into my power panel, since I did not have the auto transfer switch.


When I am plugged into 50 amp, I have a feature that disconnects my inverter manually. I actually added a spare backup inverter too, since I converted my 12 volt fridge to a residential 110 that fit right into my factory cabinet . Our 12 volt would never work properly. I will take pictures tomorrow of what the factory setup was, to my two receptacles in my foward locker. And this is exactly what Jayco said that I could only use in their setup as it rolled out of the factory.
Thank you. I definitely need to take more pictures when we install all of it.
Our new inverter has an auto transfer switch, but we can also turn it on/off manually. We're really newbies and I'd rather have someone do it for us, but getting help has been challenging, at best as it is. (thus posting on the forum).
I don't want to hear "you can't"...I need straight answers and solutions that make sense, you know?
 
Thank you. I definitely need to take more pictures when we install all of it.
Our new inverter has an auto transfer switch, but we can also turn it on/off manually. We're really newbies and I'd rather have someone do it for us, but getting help has been challenging, at best as it is. (thus posting on the forum).
I don't want to hear "you can't"...I need straight answers and solutions that make sense, you know?
To date I have wired my last four in a similar manner. The last three were not prepped for solar or an inverter. So it took a load more wiring and twisting around in tiny corners and smaller cubbies. :D So I went slowly and improved things the newer and larger my TTs got. I make no guarantees and what you see may or may not reflect your step up model from my White Hawk.

A real point of note for anyone upfitting their rvs with inverters wired manually, you do need to ALWAYS TURN OFF YOUR BREAKER FOR THE CONVERTER as you use your inverter. If not in theory you are trying to recharge your batteries by using the juice from the batteries to operate the inverter.
 
We installed the Victron MultiPlus-II 2 x120V 3000 inverter. It is a great option for RV with 2 legs of power.

It has a 2 leg 50 amp transfer switch. You connect it to the whole RV, all your devices have power. Has a 120 amp battery charger, great with lithium batteries for fast recovery. It includes power assist. When you are plugged in you can set the shore power limit and the inverter will assist the difference. Ideal when AC's are starting on a 30 amp shore power.
 

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Hum, that's a professional setup that should give you every option that you might need in your travels. I think you provided the information, and the straight answer that he ask for. I should probably keep my arrangement to myself. Good luck.
 
We have the same trailer. Your pre prep wire is in the storage compartment on the drivers side up above secured to the bedroom floor, it will be two different colour wired. It will be marked. Be careful the tags on mine were backwards (feed and load).
I installed a 2000 watt inverter, 400 ah of lithium batteries and an extra 190 watt solar panel with transfer switch. The pre prep package will give you receptacles in the bedroom, tv area . Which works for us for over night stays and my cpap machine.
I have seen the inverter installed in two locations . On the ceiling in the storage compartment and in the front storage compartment. I installed mine in the front to save on wire.
Good luck.
 
We're installing an inverter in our Eagle 321RSTS and need a little guidance (ok, a lot). Our 3000w inverter has an auto transfer switch rated at 30 amps, but obviously, we have 50 amp service...I'd like to power most/all of the RV with it. I'm not sure where the "inverter prep" is located, or where to put the inverter to power the RV. sure, we 'can' just plug in to the inverter, but that's not really what we want. Can anyone help us with photos of your setup or diagrams?
Your RV has a 50amp so it's 2 legs of 50amps each. One of the best inverter I've used is the Eg4 6000xp. It's a split phase and can peak to 50amps but constantly run 30-40amps.
If you don't have a split phase inverter you'll need 2 to power the RV. With the eg4 you can run 90% of the rv.
 
We're installing an inverter in our Eagle 321RSTS and need a little guidance (ok, a lot). Our 3000w inverter has an auto transfer switch rated at 30 amps, but obviously, we have 50 amp service...I'd like to power most/all of the RV with it. I'm not sure where the "inverter prep" is located, or where to put the inverter to power the RV. sure, we 'can' just plug in to the inverter, but that's not really what we want. Can anyone help us with photos of your setup or diagrams?
So, you bought a 3000 watt 120 volt inverter with no idea how or if it will work.
Suggestion, Make a list of what 120 volt items “must”be powered by the inverter. Get the electrical information for each. Use watts as your answers. If you only have amps at 120 volts, a 10 amp appliance would be 120 x 10=1,200 watts. Once you have everything totaled in watts, divide by 12 for battery amps. At 3000 watts, 3000/12=250 amps. With lead acid batteries, you would need (5) 100 amp hour batteries to be able to power the loads for an hour. Probably wouldn’t get that much time. A 100 amp hour battery would last maybe 10 minutes. That is of course IF you could get that many amps out of it.
Hopefully this will help you understand.
 
I presume this is your rig.
You already have lots of good advice about your rig's 50 amp split phase main service vs your inverter's 30 amp single phase service. And others have already spoken about your rig's power profile.

The fact is that you don't have and probably can't afford enough battery and solar to run your whole rig on an inverter, BECAUSE running on an inverter means running on battery.

Let's start with your 3000 watt inverter. At full tilt boogie, delivering all 3000 watts, your inverter will draw 250 amps from your battery bank. Your 400 AH of Renology Batteries can deliver about 80% of rated capacity...or 320 AH. Pulling 250 amps from any battery will also reduce its rated capacity, because rated capacity is typically done at a 20 amp draw. But hypothetically, your inverter can inhale 78% of the battery bank in the first hour.
Use this calculator to do your math: Watts/Volts/Amps/Ohms Calculator
Power is watts. Volts are always 12, because that's the nominal voltage of the battery bank.

So let's say you're going to microwave some raw potatoes so they are cooked. This takes about 10 minutes. Your micro will draw over 1000 watts continuously. So for 1/6th hour, your micro will pull at least 83 amps. So that one act alone will inhale about 14 AH from you available 320 AH in the battery bank. Now, think of running one air conditioner.
13,500 btu RV air conditioner27501250
15,000 btu RV air conditioner35001500
Forget startup. 1250 watts pulls 104 amps at 12 volts...continuously. 3 hours running just one small AC unit will eat your entire battery bank, and your solar can only produce about 1/3 of that on its best day.

Meanwhile, your 400 watts of solar, on its best day for the three hour period around noon can produce 5 AH/100 watts...or 20 AH/hour for +/- 3 hours (60 AH) and for the rest of the day, perhaps about another 60 AH. So your solar can push up to 120 AH into the battery bank on a sunny day in June when there's no shade on the panels. Late spring or early fall, those solar production numbers drop significantly.

Now another hard fact of life. I'm guessing your rig came through with a 12 volt compressor fridge...not an absorption fridge that can run on propane. Specs on a new one of these say you have a 16 cubic foot 12 volt compressor fridge. If you have a 12 volt compressor fridge, you're in for a rude awakening when it comes to 12 volt power. This is a huge fridge, and even the 10 or 11 cubic foot models eat a minimum of 35 AH/day...and in hot weather, and when getting lots of door opening/closing pumping action dumping the cold onto the floor, think more like 60 to 80 AH PER DAY!! Your solar is only making 120 on its best day.

What I'm describing is a consumption profile that can far outrun your battery and solar after you add in furnace time, lights, water pump, awning in and out, power front jacking and leveling jacks, slide, stereo, TV, and, and, and.

Getting to the point, your inverter is great for occasional use...say to nuke some popcorn when the generator is not running...or running 120 volt CPAP overnight. But you don't have anywhere near enough solar, and without it, you don't have anywhere near enough battery to be considering running your whole rig's electrical needs off an inverter.

Bottom line, you need a generator that can produce power adequate to support your 50 amp split phase demand, or a smaller generator that can do some but not all. The second you fire up even one AC, even a mid-sized (3000 to 4000 watts) generator will be working. Without a bigger generator...forget the inverter...you might not be able to run the microwave and one AC unit at the same time.

Your inverter has a place, but it's a MUCH smaller place in the power supply profile than you might think. If you are boondocking and you use it liberally, you'll be dead in the water in short order.

Use that calculator and learn more about solar and battery capacity and power consumption for 120 volt appliances. BTW, if a 120 volt appliance says it draws 5 amps at 120 volts, the hard truth is that the same appliance will draw 50 amps at 12 volts. The laws of physics are immutable. For your rig, the ideal generator would be a built-in Onan of 5000 watts or more. Regardless, given the size and character of youir rig, you're gonna need
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