Inverter Prep?

fWIW there is 12VDC air conditioners for roof top mount on RVs.

True, but they're really expensive. My current Outback is 12 years old and a lot has changed since 2011. It looks like Keystone is using 12 volt refrigerators in a lot of their trailers. I think I would still prefer the dual electric / propane version for dry camping & boondocking.
 
I've always used Xantrex inverters in the past and I still have a Prosine 1,800 watt model in my garage. I like the availability of a built-in transfer switch. The trailer I'm considering has two "inverter prep" setups and the unit I looked at had a Xantrex Freedom X 2,000 watt model already installed. I couldn't really get a good look at the wiring, but my biggest question is if the "prep" is just a Romex loop, where does it start and where does it end? Is there a subpanel somewhere? The trailer has a 50 amp main panel, with (I'm assuming) two 120 volt hot leads, L1 and L2, neutral and ground leads. There's only one breaker in the panel marked "inverter". Inverted circuits need an "in" and an "out" with a transfer switch that sends power to selected circuits when shore (or generator) power isn't available. Any ideas?

Answer to your biggest question above….the “inverter loop” starts at your electric panel and is the breaker labeled either “solar” or “inverter” outlets or some similar labeling…instead of going directly to the first outlet in the chain of inverter outlets it takes a path up toward the inverter location then “loops” back towards the first outlet in the chain…They just pulled an extra long wire to give you enough slack to cut it where it loops back towards the outlets
 
This is a brand new 2023 Outback 328RL. They are all now coming with solar and inverter prep. Some already have one inverter installed.The Xantrex inverter that's installed in this unit has a 30 amp built-in transfer switch. I guess the "AC out" side of the inverter just goes to the first of seven outlets of the inverted branch circuit and ends there, so it really isn't a loop, but more that the inverter interrupts the circuit. That won't be good enough for me as I will want some air-conditioning that's inverter powered. I see a bigger inverter, subpanel and some big lithium batteries in my future, lol...

First, you need to find out exactly which SolarFlex system is installed in the specific trailer you are buying. There are two SolarFlex systems available.

1. SolarFlex 200 (no "i") which is the basic system with no inverter installed. All that is supplied is a single 200 watt roof panel, charge controller and a loop to install a future inverter. NOTE: Many dealerships install an aftermarket inverter at the loop and sell it as a "solar ready trailer" often with a single gp24 FLA battery.....

2. SolarFlex 400i (note the "i") which is a $2K option which includes two 200watt roof panels, two roof ports (for additional installation of roof panels) an upgraded charge controller and TWO inverter loops. One of those loops (for the outlets) has an inverter installed. The other loop is intended for use with the air conditioner, but requires an air conditioner changeout (or modification for easy start system).

3. Then there isi an optional Li battery package ($2.7K) which is two "factory supplied" 100 a/h Dragonfly batteries. To add the "SolarFlex 400i and two Dragonfly 100a/h batteries is very close to $5K in optional solar equipment. NO DEALER IS GOING TO SELL THAT "as a perk"... But many do "throw in a cheap inverter and call it a complete solar ready system" (IT IS NOT !!!!)

You need to do some "serious reading" on the Keystone website to "educate yourself" on EXACTLY what is included in the trailer you're buying. If it has a SolarFlex 200 system with a "dealer installed inverter in the loop" you will need to do some EXTENSIVE and EXPENSIVE upgrades to power an air conditioner with the battery system. If it has the "basic 400i SolarFlex system, then there's a loop for a second inverter (for the air conditioner) but you'll need to change out/modify the air conditioner to use it on batteries.

Here's the link for the Keystone data on the SolarFlex systems, how they differ, what's included and more important, what you can NOT accomplish with the basic system. There's an extensive section on the limitations of the 200 system and a good explanation on WHY YOU CAN'T MAKE IT INTO A 400i system....

Spend some time learning about it "from the factory information"... WAY TOO MANY RV salesmen don't know squat about the SolarFlex differences. WAY TOO MANY RV dealerships "throw in a cheap inverter and sell the trailers are "ready to go complete with air conditioning" when in fact they simply are NOT the same as a factory equipped SolarFlex 400i system.

Here's the links:
SolarFlex 200: https://www.keystonerv.com/solarflex-200-overview
QuickStart guide: https://keystone-rv-dealer-app.cdn....-b054-1dfb3dbdc5ce_KRV_SolaFlexDF_QSG_WEB.pdf
SolarFlex 400i: https://www.keystonerv.com/solarflex-400i-overview
QuickStart guide: Same as above, but don't skip down to page 4.

In the quickstart guide, you'll find answers for two VERY IMPORTANT QUESTIONS...i

WHY CAN'T I BUILD MY SF200 TO BE LIKE A SF400i ?

and

WHY CAN'T I BUILD MY SF400I TO BE LIKE A SF600i ?

The answers to most (maybe all) of the information you need to know is included in these three links.....

I'd urge you to NOT trust every word promised by an RV salesman. They simply can't, in a 4 or 5 word answer, give you what you need to know about making a WISE CHOICE between the available "factory solar options" and the "common owner aftermarket modifications".....

Do some serious reading and don't get took by a "hungry dealer".....
 
First, you need to find out exactly which SolarFlex system is installed in the specific trailer you are buying. There are two SolarFlex systems available.

1. SolarFlex 200 (no "i") which is the basic system with no inverter installed. All that is supplied is a single 200 watt roof panel, charge controller and a loop to install a future inverter. NOTE: Many dealerships install an aftermarket inverter at the loop and sell it as a "solar ready trailer" often with a single gp24 FLA battery.....

2. SolarFlex 400i (note the "i") which is a $2K option which includes two 200watt roof panels, two roof ports (for additional installation of roof panels) an upgraded charge controller and TWO inverter loops. One of those loops (for the outlets) has an inverter installed. The other loop is intended for use with the air conditioner, but requires an air conditioner changeout (or modification for easy start system).

3. Then there isi an optional Li battery package ($2.7K) which is two "factory supplied" 100 a/h Dragonfly batteries. To add the "SolarFlex 400i and two Dragonfly 100a/h batteries is very close to $5K in optional solar equipment. NO DEALER IS GOING TO SELL THAT "as a perk"... But many do "throw in a cheap inverter and call it a complete solar ready system" (IT IS NOT !!!!)

You need to do some "serious reading" on the Keystone website to "educate yourself" on EXACTLY what is included in the trailer you're buying. If it has a SolarFlex 200 system with a "dealer installed inverter in the loop" you will need to do some EXTENSIVE and EXPENSIVE upgrades to power an air conditioner with the battery system. If it has the "basic 400i SolarFlex system, then there's a loop for a second inverter (for the air conditioner) but you'll need to change out/modify the air conditioner to use it on batteries.

Here's the link for the Keystone data on the SolarFlex systems, how they differ, what's included and more important, what you can NOT accomplish with the basic system. There's an extensive section on the limitations of the 200 system and a good explanation on WHY YOU CAN'T MAKE IT INTO A 400i system....

Spend some time learning about it "from the factory information"... WAY TOO MANY RV salesmen don't know squat about the SolarFlex differences. WAY TOO MANY RV dealerships "throw in a cheap inverter and sell the trailers are "ready to go complete with air conditioning" when in fact they simply are NOT the same as a factory equipped SolarFlex 400i system.

Here's the links:
SolarFlex 200: https://www.keystonerv.com/solarflex-200-overview
QuickStart guide: https://keystone-rv-dealer-app.cdn....-b054-1dfb3dbdc5ce_KRV_SolaFlexDF_QSG_WEB.pdf
SolarFlex 400i: https://www.keystonerv.com/solarflex-400i-overview
QuickStart guide: Same as above, but don't skip down to page 4.

In the quickstart guide, you'll find answers for two VERY IMPORTANT QUESTIONS...i

WHY CAN'T I BUILD MY SF200 TO BE LIKE A SF400i ?

and

WHY CAN'T I BUILD MY SF400I TO BE LIKE A SF600i ?

The answers to most (maybe all) of the information you need to know is included in these three links.....

I'd urge you to NOT trust every word promised by an RV salesman. They simply can't, in a 4 or 5 word answer, give you what you need to know about making a WISE CHOICE between the available "factory solar options" and the "common owner aftermarket modifications".....

Do some serious reading and don't get took by a "hungry dealer".....

This would be my 4th Outback and I agree - don't believe most of what dealers say about technical items! I will probably get a trailer with the 400i package, simply because it's pre-wired with two solar ports on the roof and has two inverter and charge controller preps in the front storage area. My days of crawling around trailer underbellies pulling wire are coming to an end...

It's interesting (and impressive) that Keystone has partnered with some of the best companies around for their solar systems. Victron Energy is one of the undisputed leaders for solar charge controllers, inverter/chargers and more. Dragonfly Energy is the parent company of Battle Born Batteries, and they make very good, very high quality, very expensive Lithium Iron Phosphate batteries. I will probably have a 1,200 amp-hour battery bank, so Battle Born would literally break the bank!
 
The problem I see is that most people think they can buy a Outback with a 200 system and next summer, upgrade it to a 400i, Or they buy a 400i system, thinking they can add a second inverter and power the existing air conditioner or, just add more panels and more batteries to "upgrade" their 400i to make it the same as a 600i system....

I've yet to meet a RV salesman who can accurately tell a customer the differences between a 200 and a 400i system, other than saying the 400i has an inverter and more roof panels and you can hook up you air conditioner to run off solar. That is "pure hogwash" as it can't be done with a pair of 100 a/h batteries and another inverter....

As an example, many RV salesmen just tell buyers they only need to add an inverter to run their air conditioner... BUT: the "air conditioner inverter loop" is 12 ga ROMEX, limits the inverter to a 2000 watt size with an A/C modification to install a soft start system (more expense) or the installation of a 3000 watt inverter (but that requires a changeout to 10 ga ROMEX).... Nearly every buyer just doesn't "think that far in advance" when picking a larger galley, larger bath and anything but that gawd-awful green countertop...... Maybe, for most, it's an emotional "want a bigger trailer and let's add solar too"... Maybe it's something else, but way too many buyers get caught short when they listen to the "sales pitch" about the 200 system and even the 400i system when the promises start flying....

Sadly, many, maybe most buyers put far too much faith in that salesman's "pitch" and never realize, until they start trying to upgrade their system (that won't do what they were told it will do) until it's too late, that salesman has moved on to sell cars or vacuum cleaners and the dealership just "shrugs its shoulders" at the promises not kept......

Do your "homework" and know what you're getting (and more importantly, what you're NOT getting) before signing the mortgage !!!!!
 
[I've yet to meet a RV salesman who can accurately tell a customer the differences between a 200 and a 400i system, other than saying the 400i has an inverter and more roof panels and you can hook up you air conditioner to run off solar. That is "pure hogwash" as it can't be done with a pair of 100 a/h batteries and another inverter....]

Well, technically it IS possible but the A/C would only run for less than an hour and the batteries would be dead. The other day I was playing around with my 1,800 watt Prosine, a Renogy 100AH AGM battery and a portable air conditioner. On low speed (7,000 BTU), it was pulling between 70 and 80 amps. I drained the battery from full to 80% in about 10 minutes.

[As an example, many RV salesmen just tell buyers they only need to add an inverter to run their air conditioner... BUT: the "air conditioner inverter loop" is 12 ga ROMEX, limits the inverter to a 2000 watt size with an A/C modification to install a soft start system (more expense) or the installation of a 3000 watt inverter (but that requires a changeout to 10 ga ROMEX).... Nearly every buyer just doesn't "think that far in advance" when picking a larger galley, larger bath and anything but that gawd-awful green countertop......]

And this is where knowledge and experience really come in. The average buyer knows little to nothing about AC or DC electrical systems, and why should they? They want to buy a pretty new toy so they can go out and have fun with the family! They will be so far out of their element that they're going to trust whatever the sales person tells them...until reality sets in, then they'll buy a "really quiet" contractor grade generator to solve the problem. I was at our membership campground yesterday and an F250 or 350 pulled in with a ridiculously long toy hauler, music blasting through the open windows, and a contractor generator RUNNING on a cargo carrier mounted to the back of the trailer. "Please don't park over here", "please don't park over here"...

The second inverter prep on the Outback (probably for the smaller 13,500BTU bedroom A/C unit) is wired with 12 gauge, 20 amp Romex connected to a 20 amp breaker at the main panel. That setup would probably work with a 2,000 watt inverter, since the Coleman Mach 10 Quiet Soft Start uses max 13.6 amps. I would need to change that to a 30 amp circuit with a subpanel for the A/C and the microwave oven because who the hell wants to dry camp without a microwave? :LOL::LOL:
 
I have a 2022 Passport GT 2951BH and about to install the Renogy Pure Sine Wave 2000W inverter.
It doesn't have an AC internal automatic transfer switch.

I talked to a friend (he did a similar inverter setup on his catamaran) and we came up with this diagram, hopefully it can help others
rv-inverter-loop-diagram.jpg

The automatic transfer switch should have the shore power (yellow hot line) as a priority over the inverter lines.

I'm going to use the Furrion 30 AMP Auto Transfer Switch but the internal layout is identical.

Yellow cord hot goes the bottom right (SHORE POWER CORD)
Yellow cord cold goes the top left (LINE OUT)
Inverter cord goes to the top right (GENERATOR)

qu340859_800.jpg


qu340859_2_800.jpg
 
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I did purchase the 328RL that I was referring to in this thread, and unfortunately I have to say that it probably has more manufacturer defects than the three previous Outbacks combined that I've owned since 2006. Very poor construction quality with every plumbing connection leaking, loose screws, nuts, bolts and so on. Just yesterday I took a close look at the electrical system to figure out what loads were on which circuit, and it's a hot mess. Are you going to be using a subpanel for your inverted circuits or are you going to provide inverted AC power for your entire main panel? If so, you'll need to remember to turn off the breaker for the AC-DC converter when running off of your batteries or you'll create a loop from batteries-->inverted AC power-->converter-->DC charging of the batteries, and that will discharge your batteries in short order. You will also need to turn off the breakers for any other AC loads you don't want to use when running on battery power (or just remember to not use those loads). My trailer has one Xantrex 2000 watt inverter that feeds six outlets and is GFI protected by the first outlet in the circuit. The Xantrex has a built-in 30 amp transfer switch, is wired with 12 gauge Romex (20 amp), from the main panel and is fed by a 15 amp breaker. "What the....?". So the genius who forgot to caulk under the shower door frame obviously installed the inverter and decided to derate the circuit a couple of times because he ran out of 10 gauge Romex (30 amps) and 20 amp breakers. Good luck and remember not to hold the end of the wire in your mouth unless the power is turned off!
 
There is no circular charging loop because the inverter loop cord is not charging the batteries or feeding the charger but is going to 120 VAC outlets.
The MPPT solar battery charger controller is another separate circuit.
That's why Keystone left the yellow inverter prep cord, for easy and correct inverter installation.
 
Just 2 comments:


1. I'd enhance that diagram to have a actual shutoff instead of using the fuse.
2. Check the fuse sizing as the 2000 inverters I've seen/installed recommend 250A
 
Just 2 comments:


1. I'd enhance that diagram to have a actual shutoff instead of using the fuse.
2. Check the fuse sizing as the 2000 inverters I've seen/installed recommend 250A

Hi, thanks for the comments.
What do you mean by actual shutoff?
The part I'm using is an Amp Circuit Breaker, not a fuse.
711f3exwTLL._SL1500_.jpg


As for 250A vs 300A:
My logic was the following:
The Renogy 2000W supports 2000W continuous power and 4000W peak power.
At 12 VDC this means a current of 4000 / 12 ~= 333A (but let's call it 300A)
250A (which is ~3000W) would cause the circuit breaker to trip on peaks which the inverter considers with normal operations.
I want the circuit breaker to protect against a catastrophic failure with very high current that could happen when there is some internal short or malfunction in the inverter.

I think the circuit breaker rating should match the actual product. Not all inverters are equal.

The inverter I got:
https://www.renogy.com/2000w-12v-pure-sine-wave-inverter-with-power-saving-mode-new-edition/

That been said I'm open minded and not rulling out changing the rating to 250A
 
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I understand. Most manuals/installation guides will use the term "fuse" but the breaker is what I use too. This is to protect the wiring/buses,etc and should be sized at about 125% of the continuous amps. So it may/maynot be correct depending on what you install.


I always use a battery shutoff next to my inverter and put the breaker close to the battery.


Attached is the generic (xantrex/keystone) diagram that I posted as well as others years ago. The breakers/fuse/wiring all change depending on the size of the inverter. Also the type of switch/disconnect I'm referencing.
 

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I see, thanks.

Did some more reading, I just changed the diagram to 250A.
For me the circuit breaker within the RV basement is enough. It is pretty close to the battery and also to the inverter, and is protected from the elements.
I don't want to over complicate things.

Updated diagram:
rv-Inverter-loop-250A.png
 
.....
The inverter I got:
https://www.renogy.com/2000w-12v-pure-sine-wave-inverter-with-power-saving-mode-new-edition/

That been said I'm open minded and not rulling out changing the rating to 250A




I would call them before you do this install! I looked at the installation manual for this inverter and something does not look correct in there. The fuse sizing looks correct min. of 200A (250 = 125%). BUT what does not look correct in this manual is the wire gauge for the battery. It has a gauge of 2 minimum and I know that 2000W inverters require 2/0 min and higher depending on the length.
 
There is no circular charging loop because the inverter loop cord is not charging the batteries or feeding the charger but is going to 120 VAC outlets.
The MPPT solar battery charger controller is another separate circuit.
That's why Keystone left the yellow inverter prep cord, for easy and correct inverter installation.

Sorry, it was late and after I logged off, I thought "oh, he's only inverting one circuit, in the same manner that Keystone does". However, microwave ovens are usually on their own circuit because they are a large load and can have big power spikes, that's why I was thinking you were inverting more than one circuit. This may work, but when you use the microwave, you may need to turn off any other loads on that single circuit or you'll trip the breaker. A 2000 watt inverter can get maxed out pretty quickly.

I removed the factory provided 2/0 cable from the tongue of the trailer that went to the inverter and replaced everything with 4/0 that already had. I put bus bars on the tongue, inside waterproof project boxes, and also inside the storage compartment. My new 280 amp-hour LiFePO4 batteries are in the storage compartment and they connect to the bars in the compartment, then a length of cable connects those to the bars on the tongue. Yes, 4/0 cable going out to the tongue is overkill, but I already had it, so I used it. I removed and tossed the "Future Solutions BMI box" because it was nothing more than bus bars in a box, along with the Victron shunt that comes with the 400i system (I already had a new shunt to use inside the storage compartment). It was also filled with water and had rusty nuts / bolts. I kept the "Giggy Box" on the tongue and ran its positive cable to the new bus bars on the tongue. I'm also using breakers as shut-off switches, even though I do have actual switches. I just need to install them because I always use a combination of breaker / fuse as close to the batteries as possible, then an on / off switch. Since I used 4/0 cable, I installed a 300 amp breaker in the compartment, between the batteries and the bus bar. I've tested everything and it's working perfectly. I'll post some photos so you can get a better idea what I'm talking about.
 
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I see, thanks.

Did some more reading, I just changed the diagram to 250A.
For me the circuit breaker within the RV basement is enough. It is pretty close to the battery and also to the inverter, and is protected from the elements.
I don't want to over complicate things.

Updated diagram:
View attachment 46202

I would buy two of them then and carry a spare. I've found the circuit breakers to be not the best quality in terms of durability so I would anticipate that reset arm failing when turned on/off as a switch.
 
I have a 2022 Passport GT 2951BH and about to install the Renogy Pure Sine Wave 2000W inverter.
It doesn't have an AC internal automatic transfer switch.

I talked to a friend (he did a similar inverter setup on his catamaran) and we came up with this diagram, hopefully it can help others
View attachment 46199

The automatic transfer switch should have the shore power (yellow hot line) as a priority over the inverter lines.

I'm going to use the Furrion 30 AMP Auto Transfer Switch but the internal layout is identical.

Yellow cord hot goes the bottom right (SHORE POWER CORD)
Yellow cord cold goes the top left (LINE OUT)
Inverter cord goes to the top right (GENERATOR)

qu340859_800.jpg


qu340859_2_800.jpg

Here's my install, that is still in progress. When I first began, the weather in the San Diego mountains was getting bad, so I was rushing a bit, trying to finish before it started snowing. I still need to move some things around and put battery cable covers on the ends to prevent shorting everything out. I replaced the stock 30 amp charge controller with the 50 amp model as I will be adding more solar panels on the roof, for a total of about 1,100 watts. I think I will need to put the stock controller back in because I discovered that the solar panels provided by Keystone are 24 volts, not 12 as I expected. My other panels are 12 volts and I will connect them in series, but to avoid differences in voltage / current, I'll put the stock panels back on the 30 amp charge controller and everything else on the 50 amp controller.

I added a separate Victron 30 amp charger to give me another option besides solar or being plugged into shore power. If I'm boondocking, I can use just my quiet 1,000 watt generator and plug the charger into it using an inlet in the front cap that I still need to install. The Xantrex and Victron remote displays will be installed in the wall inside the trailer where all of the switches & tank gauges are located. The Xantrex 2,000 watt inverter can surge to 4,000 watts for 5 seconds, so I'm going to stick with the 300 amp breakers for the batteries to bus bar connection and the bus bar to inverter connection. I also need to fit on-off switches in there somewhere. There is a second inverter prep in the compartment that I'm pretty sure is for the main air-conditioner, but that will be a project (and a 3,000 watt inverter) for another time Let me know if you have any questions about the install.

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I use my basement too frequently so I relocated my inverter and batteries under the bed. 2/0 from the batteries to the breaker and shunt, 4/0 to the inverter, 4 awg to the tongue. Really helped with lowering the tongue weight as mine was excessively heavy. Bedroom AC has a soft start and I've been able to get just over 5hours of Air Conditioning with 600ah. Trailer came with solarflex 200, added 2 more panels, bumped up the voltage (series) to reduce amps from roof and keep safe for the guage. Now pushing 640watts of solar, don't want anymore. Upgraded the charge controller. Next step is to install a 20amp romex line from the inverter to an auto transfer switch serving the air conditioner. Only problem is I can't use any outlets while the AC is running (possible overloading the inverter), unless I splurge for another inverter.
 

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I am just now looking at my inverter prep and the romex loop I understand, what are the additional wires for that are wire nutted together in my 200rlwe
 

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