Installing 3000 watt inverter into 5th Wheel

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ddrews2

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Recently purchased a 30ft 5th wheel. Anyone have suggestion on best brand of inverter to install? I need to be able to install a remote on/off switch inside from the inverter and hook up to my AC/DC panel so I can use all the electrical outlets in the trailer. I understand I can buy the necessary cables at Home Depot, but where do I get the remote switch to install inside the trailer? I see a lot of different inverters on Ebay, is that a good place to buy? Will the 3000/6000 watt inverter be enough to run my 13,500BTU AC??Planning on recharging my (2) deep cell batteries during the day with a generator so I can stay silent in the evenings. Help!
 

Ned

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Xantrex has a full line of RV inverter/chargers to choose from.  Both modified and pure sine wave models.  The remote switch is part of a remote control and monitoring panel for the inverter/charger that not only turns the units on and off but also monitors the state of your batteries.  Rewiring your outlets for inverter use is not a simple job, but can be done by moving the circuits to a secondary distribution panel fed from the inverter and feeding the inverter/charger from one of the existing circuits.

You need to calculate your AC power requirements to determine the size of inverter you need, which will then determine how many and what size batteries you should have.  There are some articles in our library that can help with that.

You won't be able to run your A/C from the inverter, you'll have to use the generator.

As for buying on Ebay, I've had good luck there but be sure to investigate the seller and for such a large ticket item, make sure the return policy is satisfactory in the event of a problem.
 

Gary RV_Wizard

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You  have a couple fundamental choices to make upfront. But first a reality check...

Your inverter can deliver only as much power as you have in your battery bank. A 3000 watt load at 120 VAC is about 25 amps of AC. To produce this much AC, the inverter draws about 10x that amperage in DC from the batteries. In other words, 250 DC amps at 12 volts. A pair of 6V golf cart batteries has a maximum capacity of about 220 amp-hours but the voltage will fall below usable levels before you get anywhere near that much from them, especially at such high current levels.  Battery capacity is rated at a 20A continuous draw; it is much less of the current draw is higher than that.  Therefore you need a very large battery bank if you expect to use anywhere near that much power.  Your a/c draws somewhere between 10 and 14 AC amps when running, so it is less than a 3000 watt load, but it is still a major power hog. Most likely the battery voltage will drop below the inverter's minuimum everytime the a/c compressor tries to start. Nobody has found it practical to run an a/c on an inverter, even with 6 golf cart batteries online. You probably also do not want to run your electric water heater, washer/dryer or other hifg demand appliances on the inverter. Even a microwave will draw a tremendous amount of battery current if it runs for more than a few minutes. So you need to think seriously about how much power you expect to draw at one time (max amps) and how much total power you  will need between charges (kilowatt hours or amp-hours) and whether you can provide enough battery capacity to achieve that.

The major upfront choice is to get an inverter/charger to replace your existing converter/charger or to keep your existing converter/charger and add an inverter (without a charger) to provide AC power. Another is whether you want pure sine wave power or the less expensive modified sine wave technology.  The most elegant (and expensive) solution is an inverter charger such as the pure sine wave Xantrex RS3000. See http://www.partsonsale.com/rs3000.html  But you can couple a standalone inverter with your existing converter/charger without a whole lot of difficulty, assuming you have some electrical skills. That's how my rig is set up.

You must assure that there is never more than one AC power source active in your RV at the same time. It is most important to never allow shore power or genset AC to feed power to the AC circuits at the same time as the inverter. That means a switch, preferably an automatic one, to switch the power supply between the potential sources. These are called transfer switches and can be found on Ebay or through most places that sell inverters or gensets.  However, a simple alternative is to simply plug the shore power cord into the inverter output when desired. That makes sure you are not using shore power when the inverter is on, and vice versa.

A remote switch for an inverter is usually easy. The intergrated inverter/chargers will either come with one or offer it as an option. I t is usually integrated with a display that shows battery amp-hours as well as AC output. The Link 2000 is an example.  If you use a standalone inverter, it will have an on/off switch on its face plate. It's a simple matter to go under the covers to splice a wire into the switch circuit and run it to a remote switch at a place of your choosing. The wiring is simple - you aren't switching the entire load - just tripping a relay insde the inverter. 20 gauge wire and a panel switch are all you need. I have two inverters wired that way (I have a 2000 watt main modified sine inverter and a separate 150 watt pure sine inverter I use to power sensitive electronic equipment).

Think about this for a bit and then ask more questions.
 

John From Detroit

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I will second Ned's statement that Xantrex has a nice line of inverters.

I choose a true-sine wave (prosine 2.0) for my Motor Home,  Runs the televisons and all related electronics, the Microwave and all but 3 outlets in the motor home  Does a good job

The Xantrex prosine line meets all your remote control requirements, and the true sine wave inverters like my Prosine give out cleaner power than what I get out of the wall here in the house.

I would avoid the "Modified sine wave" inverters,  Some things do not much like them and they make a lot of radio noise
 

ddrews2

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Really appreciate you taking the time to give me such detailed information....helps me sort out what I should do. I found Inverter/chargers a little pricy. Can you recommend a reliable brand and model that would still hook up to my AC/DC panel with a remote switch that doesn't have the battery charging feature?
 

John From Detroit

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One thing you need to know about the inverter/charger combnation is that it's much more than just an inverter

Basically you have 3 or 4 parts, The first part is the inverter, of course, and then the charger, cause once you do all that inverting you have to re-charge the battery.  This is very important.  Than you have a switch to select between recharge/direct power feed to load, or inverter to load power  That part is kind of expensive all by itself.

If you want to do it with just an inverter than again, Xantrex has a few models, Again, I prefer a true-sine wave to a modified sine wave, but since it's a trailer consider an inverter with an outlet that matches the power plug on the trailer and simply plug in to the inverter when you want inverter power, or the post at the campsite if that's your option

Saves the cost of a switch... Switches are expensive for reasons that have nothing to do with hardware
 

Bob Buchanan

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ddrews2 said:
Recently purchased a 30ft 5th wheel. Anyone have suggestion on best brand of inverter to install? I need to be able to install a remote on/off switch inside from the inverter and hook up to my AC/DC panel so I can use all the electrical outlets in the trailer. I understand I can buy the necessary cables at Home Depot, but where do I get the remote switch to install inside the trailer? I see a lot of different inverters on Ebay, is that a good place to buy? Will the 3000/6000 watt inverter be enough to run my 13,500BTU AC??Planning on recharging my (2) deep cell batteries during the day with a generator so I can stay silent in the evenings. Help!

Hello ddrews:

When I purchased my 1st RV 11 years ago, I added a StatPower (now Xantrex) 1500W Inverter and 40Amp 3 stage charger. Each time I go to a different rig I bring them forward (now on my 4th) -- so they have been chugging along now for many years. Also, my install is pretty basic and allows me to invert all through the coach outlets. Here's what I do:

First I mount the two units as close to the battery bank as possible. The lines to the battery need to be as short as possible vs. the AC coming from the inverter due to line lose. I have been lucky in each coach to find an AC outlet to plug the charger in while keeping it very close to the battery bank. I then place the Inverter right beside the charger and begin the tougher part.

My "poor man's double pole double throw switch" has worked well for me. I use this switch to control the AC input to my house converter.? I purchase 2 normal 30A switches. I then connect the AC from the inverter to one of the switches and the input AC from shore/genset to the other. I mount the two switches flush against each other, with one upside down from the other. I drill a small hole thru both switch levers and place a metal dowel thru both. Now when I throw both switches with the dowel, it turns one on while turning the other off. This way one line cannot feed back down the other line. As I say, this has worked for 11 years now -- and costs less than $25-$40 if I recall.

The next chore is to isolate the critical energy drawing breakers. For example, from my "Stuff that draws AC that I don't really need while dry camping" list, I make sure that items such as the charger are on a braker that I can turn off when I turn the inverter on. My list will vary from coach to coach -- but will also include my shifting the frig to Propane vs. AC. My electric hot water heater prob is on that list as well.

Finally, I want to run down all the other stuff that does phantom AC draws. For example, the DirectTV Tivo box, TV sets, and printers all draw power even tho they are turned off. From there, I try to place each group on a separate power strip so I can kill them all if need be. As an example of how this might work, in my last Class C rig, I had all the up front entertainment stuff on one strip, my desktop computer system on another, and my laptop (for dry camping) on another. It is amazing how much current all of those devices can draw altogether.

Year? before last a QZ I purchased a Xantrex Trace meter for my setup. I mount if very close to the inverter and charger. One readout tells me how many Amps are coming into or out of the batteries at any point in time. This was invaluable in finding those phantom loads. I would simply note the reading, turn on the suspect unit, and see if it increased the draw -- and by how much.

I don't think you would want to even consider running an A/C via an inverter. Even if it would run it, the batteries would drain very fast. Recharging batteries takes a lot longer to do than running them down.? :) That is another reason to make sure you isolate and remove items that draw power that aren't being used.

BTW, over the years I have gotten input from RV Forum members Lou, Jayne, and Wally on the best way to do this sorta thing. They are really great a getting the job done for the least amount of money. And the actual wiring of the poor man's double pole I have done by a qualified electrician.
 

ddrews2

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Great! You are really helping me setup my 5th wheel for my personal preference. I will definitely buy pure sine wave and not modified. I will? not use my AC or Microwave with the inverter.

Currently when dry camping; I use one Honda EU2000i generator, (2000 watts), in the evenings. I use two Honda EU200i, (tandem setup), when using the AC or microwave. I found the AC and microwave really suck the power and crank both generators up to full capacity (4000 watts). Cannot run both of those at the same time!

I do want to operate my laptop, TV, DVD/VCR, radio/CD player, satellite receiver, internet modem, coffee maker, and cell phone charger via 110v outlets in the evenings. (Not all at same time, of course) .

I have two new large 12V deep cycle batteries hooked up tandem. I don't want to go to a 4 batteries because of added weight and space. These two batteries work fine for days at a time with my 400 watt (cigarette lighter) inverter in the entertainment center. This operates my TV and DVD/VCR player only.

John in Detroit is using the Xantrex true-sine wave (prosine 2.0) Do you think I would be able to use the Xantrex Sine Wave Inverter 1800 watt and still achieve my goals? I would mount the inverter next to my batteries, run the remote switch inside the trailer (approx. 4ft) and plug my existing 30 amp trailer power cord into the inverter (using 110v adapter like I do with my generator). Would that work? Or would I screw everything up if the converter tries charging the batteries I am drawing from???
 

Tom

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If it's any help, we have a file called Installing an inverter in our forum library. Just click the Library button above and select Tech topics. It's written generically, so you could substitute any inverter/charger, remote panel and batteries of your choice.
 

Karl

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John in Detroit is using the Xantrex true-sine wave (prosine 2.0) Do you think I would be able to use the Xantrex Sine Wave Inverter 1800 watt and still achieve my goals? I would mount the inverter next to my batteries, run the remote switch inside the trailer (approx. 4ft) and plug my existing 30 amp trailer power cord into the inverter (using 110v adapter like I do with my generator). Would that work? Or would I screw everything up if the converter tries charging the batteries I am drawing from???

The 1800 does not have a  100 amp, 3-stage charger like the Prosine 2.0 does but, aside form that, the difference between the two is only 200 watts - not a biggey.

No, you can't use the converter to recharge the batteries that you're running your inverter on. Physically it may be possible, but you would be powering the converter from the inverter which runs off the batteries you're trying to charge. Nice trick, but no workee. That would be perpetual motion.

You didn't mention what type/size converter you have or are considering getting. It definitely should be a 3-stage converter to prevent cooking your batteries. If you don't have one, you may want to consider an inverter that has a charger built in, that way the inverter will monitor the battery status and take care of the charging for you when you're on shore power or generator.

Lastly, there's nothing wrong with a modified sine wave inverter. Some things may not work (or work as well), but as Gary stated:
I have two inverters wired that way (I have a 2000 watt main modified sine inverter and a separate 150 watt pure sine inverter I use to power sensitive electronic equipment).
While a true sine wave inverter is a better choice, they're about twice as expensive as the other kind, and you don't really need a full 2kW or 3kW of sine wave power to meet most of your needs.
 

John From Detroit

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Should work for most things, won't run AC may have a problem with a Refrigerator, Hot water heater and/or Microwave (microwaves sometimes want true sine waves)

But for everythign else it should work fine

I use a pair of 8-D size deep cycles to run my inverter when parked, (The prosine 2.0) it can run the microwave, all the "electronics" but does not power the AC, fridge or water heater
 

Gary RV_Wizard

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Do you think I would be able to use the Xantrex Sine Wave Inverter 1800 watt and still achieve my goals? I would mount the inverter next to my batteries, run the remote switch inside the trailer (approx. 4ft) and plug my existing 30 amp trailer power cord into the inverter (using 110v adapter like I do with my generator). Would that work? Or would I screw everything up if the converter tries charging the batteries I am drawing from???

Short answer is yes, but some caveats...

You should unplug your converter when using the inverter as you describe.  It is simply wasting power and the lower the battery charge gets the worse the waste becomes, since it is drawing power from the batteries in its to attempt to put a further charge into the batteries. It's a death spiral for your battery charge, but it doesn't actually harm anything.

If you use the inverter as you describe, you will probably also want to make sure you force your refrigerator into LPG mode (reduces invetter draw). Also make sure your water heater is in LPG mode - should you forget and leave the AC heater switched on, you can flatten the batteries in no time.

For the laods you described here, your max power draw is about 1000-1200 watts, so an 1800 watt inverter is more than enough. You could probably get by on  less.
 
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