Inverter install and Converter modification on 22MLE

[Melsman]

Hello All,

I'm in the process of designing and installing an inverter as an alternate 120v line source in my Imagine XLS 22MLE (which uses a WF-8735 converter), and I've decided that a Go Power TS-30 switch will accomplish the automatic switching I want between inverter power and shore/generator power. However, I want to verify that I have a firm understanding of how to wire my WFCO WF-8735 converter to function properly with the inverter using the TS-30 to control the switching.

I have spent much time on this forum (and other sources) trying to verify and validate my wiring scheme (including reading TucsonJim's excellent article), but have not found an adequate answer. So, let me try to describe how I visualize wiring my converter to work with the inverter and transfer switch - (See attached diagram)

I will be following the suggested wiring diagrams for the WF-8735 and the GP TS-30 for connecting the inverter to the system. To connect the WF-8735 converter, I will be removing the shore power input from the unit and wiring it into the TS-30's N.O. Hot and N.O. Neut. terminals. I will then wire the 120v supply for the converter/charger section of the WF-8735 to the N.O. Hot and N.O. Neut. terminals. Finally, I will wire the main circuit breaker in the breaker bus ("AC Panel") to the COM Hot and COM Neut. terminals. The 2500W inverter will be wired into the N.C. Hot and N.C. Neut. terminals of the TS-30.

Do I have this right? Any comments or corrections are appreciated.

Melsman

[acoleman43]

Melsman You may not need a ATS at all. What inverter are you looking at? Are you intending to power the entire distribution panel through the inverter?

Many inverters have a built-in ATS. If you are planning to power the entire distribution panel, I would look at a stand-alone inverter that has a built-in ATS. It makes it simple. Just bring shore power/generator directly to AC input of the inverter, then AC output from inverter to main breaker of the main distribution panel. The inverter will switch between shore power and inverter automatically. You will need to run a cable from battery(s) to DC input of inverter as well.

If you are planning to power specific devices/circuits with the inverter, that's handled very differently.

In other words it would be helpful to understand your entire system and intention to give you a better answer

[Melsman]

Thanks for the response- Yes, I want to power the entire distribution panel with the inverter. I had originally considered an inverter with a built-in ATS but decided against it given the limitations on inverter types and availability. Plus, I like to keep subsystems modularized (if possible/practical) so that replacement or repair expenses are minimized. But that’s my preference; others may disagree.

Melsman

[Country Campers]

If the converter is on its own breaker you could just turn the breaker off when the inverter is to be used.

Brian

[howson]

Melsman

Not sure I understand. A converter uses 120vAC to charge the battery bank. The battery bank provides the power to an inverter to generate 120vAC. Using an inverter to power a converter sets up a self-defeating loop.

Bottom line: when the inverter is providing 120vAC to the RV the OEM converter must be isolated from the 12vDC circuit.

Echoing acoleman43 input, having a inverter/charger with a built-in ATS solves the entire issue--they have built-in ATS' and have their own converter, too, that automatically switches off when acting as an inverter.

If you do any searching of this forum you'd know I'm an unabashed Victron fanboy. They are not the cheapest but are superb equipment. Once the pain of writing the check is a memory there is a high probability of satisfaction with the purchase. (Not criticizing your choice...just giving an alternative perspective from an owner who has purchased and installed their own Victron system.)

Howard

[TedS]

Like howson said powering the converter with the inverter is self-defeating. That loop has batteries powering the inverter powering the converter charging the batteries. That's an impossible perpetual motion system.
The batteries need an independent charging source.

[Jlawles2]

All, it took me a minute to decipher the diagram.

It appears that he wants to intercept the charger wires at the incoming connection to shore power and wire them to the charger port on the ATS. This way the ATS kills power to the charger if not on generator or shore power at the bottom left of the ATS. The bottom right is output power to the WFCO panel, and note that the OP circled the wires for the converter (originally tied to shore power) and tied them to the upper left of the ATS.

[acoleman43]

All, it took me a minute to decipher the diagram.

It appears that he wants to intercept the charger wires at the incoming connection to shore power and wire them to the charger port on the ATS. This way the ATS kills power to the charger if not on generator or shore power at the bottom left of the ATS. The bottom right is output power to the WFCO panel, and note that the OP circled the wires for the converter (originally tied to shore power) and tied them to the upper left of the ATS.

Good point. I have to assume there are solar panels to charge the batteries, otherwise nothing will be charging the batteries when not connected to shore power/generator.

Melsman out of curiosity, what inverter are you looking at?

[TedS]

Jlawles2 thank you for clarity. I see the converter is independently connected to shore input and not through the power panel. The scheme should work.

[Yoda]

Hello All,

I'm in the process of designing and installing an inverter as an alternate 120v line source in my Imagine XLS 22MLE (which uses a WF-8735 converter), and I've decided that a Go Power TS-30 switch will accomplish the automatic switching I want between inverter power and shore/generator power. However, I want to verify that I have a firm understanding of how to wire my WFCO WF-8735 converter to function properly with the inverter using the TS-30 to control the switching.

I have spent much time on this forum (and other sources) trying to verify and validate my wiring scheme (including reading TucsonJim's excellent article), but have not found an adequate answer. So, let me try to describe how I visualize wiring my converter to work with the inverter and transfer switch - (See attached diagram)

I will be following the suggested wiring diagrams for the WF-8735 and the GP TS-30 for connecting the inverter to the system. To connect the WF-8735 converter, I will be removing the shore power input from the unit and wiring it into the TS-30's N.O. Hot and N.O. Neut. terminals. I will then wire the 120v supply for the converter/charger section of the WF-8735 to the N.O. Hot and N.O. Neut. terminals. Finally, I will wire the main circuit breaker in the breaker bus ("AC Panel") to the COM Hot and COM Neut. terminals. The 2500W inverter will be wired into the N.C. Hot and N.C. Neut. terminals of the TS-30.

Do I have this right? Any comments or corrections are appreciated.

Melsman

Make it easy on yourself. I went down the same road you taking and after looking at all the parts and future adaptability - Well - Just get a Victron Energy inverter / charger. I have the 3000 model https://www.victronenergy.com/invert...48v-800va-3kva Feeding my entire 30A system

You then just take your shore power 120V wire to it and a new 120v output wire back to your distribution panel - that's it, and disconnect your existing converter. The multiplus converter is more powerful and can be custom programed by you for lithium or other batterys. It also has a power boost feature for low voltage situations. Mine works very well. It survived the rough Alaska trip and worked like a champ when we boon docked. I added the Touch 50 screen and the Cerbo GX to tie my MPPT solar controllers and BMV 712 to monitor power and battery state,, but I see that Victron has some new products that offer better Bluetooth communication with less parts, but I will leave that to the experts to advice if you wish to go this path. However the Multiplus can be stand alone too without the add ones.

The upside is if it ever fails all I need to do is pull the 120 connections at the multiplus, tie them together and re connect the stock converter and I am back to stock.

Hope this helps
Keith

[Melsman]

Lots of thoughtful responses; thanks, everyone! I greatly appreciate it.

Country Campers - You are correct; I could do it through a dedicated circuit breaker and other switching (@TucsonJim describes a similar set-up in his document), but since I will not be the only person operating this system, and sometimes my brain doesn't work the way it should, I wanted it to be automatic.

Jlawles2 - Thanks for helping everyone decipher my intent via the diagram. The inverter-charger-battery feedback loop had me concerned initially until I figured out how to do it through the ATS. The theory is sound, but the actual wiring solution was where I was unsure and wanted to get feedback. The other aspect I was stuck on was powering the 12V bus when the converter was off-line, but then it dawned on me that the batteries back-feed through the charging line to power the 12v bus... which is what it does whenever the converter is not connected to shore power! (duh!)

howson and Yoda - The Victron systems are top notch, no doubt. And the manufacturer support and warranty appear to be superb - a critical point in my decision matrix. However, at 3X the cost of other viable products, the expense is hard to justify - at least for my pocketbook for a part-time camper. The ATS Inverters alone would eat up my entire project budget. And why Yoda would I ever want to make things easy on myself?

I should probably state that my design goal here was to seamlessly integrate an inverter into the entire AC system without replacing any of the current stock components, thus keeping my costs down and operational simplicity high. My feeling is that there are many folks out there that have the same desire, but I've not found anyone who documented that process. I did find a few that plugged their inverters directly into their shore power and then, through a series of circuit breakers and switches, defeated the inverter-charger-battery feedback loop. However, I wanted a more elegant (and idiot-proof) system since I can be an idiot at times.

acoleman43 - You are correct; there is a solar charging system (the stock 165W panel/Furrion MPPT that was factory installed on the MLE - a nod toward the 12v refrigerator I suspect), to charge the batteries when off shore/gen power. I didn't go into the entire system design since it wasn't relevant to my question, but if there is interest, I can supply a diagram of the entire system. (Perhaps in a separate thread once the design is built and functional.) As for which inverter I'm going to use, I haven't yet decided. I have decided upon a pure sine wave 2500W inverter, but am researching manufacturer support and reliability before making my final decision.

@TedS - Thanks; that's the feedback I was looking for. I want to make sure my concept wiring was viable. I've gotten similar feedback from Go Power and am waiting for a response from WFCO.

Again, thanks to all for the excellent suggestions and information!

Melsman

[Yoda]

Lots of thoughtful responses; thanks, everyone! I greatly appreciate it.

Country Campers - You are correct; I could do it through a dedicated circuit breaker and other switching (@TucsonJim describes a similar set-up in his document), but since I will not be the only person operating this system, and sometimes my brain doesn't work the way it should, I wanted it to be automatic.

Jlawles2 - Thanks for helping everyone decipher my intent via the diagram. The inverter-charger-battery feedback loop had me concerned initially until I figured out how to do it through the ATS. The theory is sound, but the actual wiring solution was where I was unsure and wanted to get feedback. The other aspect I was stuck on was powering the 12V bus when the converter was off-line, but then it dawned on me that the batteries back-feed through the charging line to power the 12v bus... which is what it does whenever the converter is not connected to shore power! (duh!)

howson and Yoda - The Victron systems are top notch, no doubt. And the manufacturer support and warranty appear to be superb - a critical point in my decision matrix. However, at 3X the cost of other viable products, the expense is hard to justify - at least for my pocketbook for a part-time camper. The ATS Inverters alone would eat up my entire project budget. And why Yoda would I ever want to make things easy on myself?

I should probably state that my design goal here was to seamlessly integrate an inverter into the entire AC system without replacing any of the current stock components, thus keeping my costs down and operational simplicity high. My feeling is that there are many folks out there that have the same desire, but I've not found anyone who documented that process. I did find a few that plugged their inverters directly into their shore power and then, through a series of circuit breakers and switches, defeated the inverter-charger-battery feedback loop. However, I wanted a more elegant (and idiot-proof) system since I can be an idiot at times.

acoleman43 - You are correct; there is a solar charging system (the stock 165W panel/Furrion MPPT that was factory installed on the MLE - a nod toward the 12v refrigerator I suspect), to charge the batteries when off shore/gen power. I didn't go into the entire system design since it wasn't relevant to my question, but if there is interest, I can supply a diagram of the entire system. (Perhaps in a separate thread once the design is built and functional.) As for which inverter I'm going to use, I haven't yet decided. I have decided upon a pure sine wave 2500W inverter, but am researching manufacturer support and reliability before making my final decision.

@TedS - Thanks; that's the feedback I was looking for. I want to make sure my concept wiring was viable. I've gotten similar feedback from Go Power and am waiting for a response from WFCO.

Again, thanks to all for the excellent suggestions and information!

Melsman

OK one thought that may have been overlooked. When using the Inverter you are disabling the converter which is only used when on Shore power. Do you have enough Solar and battery storage to handle the inverter power demand and how will the 12V fridge respond to low voltage situations that may result. I don't have a 12V fridge, but vaguely remember issues in low voltage situations. Just a thought - can you separate the solar and one battery from your inverter (I assume your adding battery capacity) so the fridge is not affected by inverter usage?

On thing I like about the multiplus is you can program it to shut down when battery voltage gets to a certain level, so you still have power to hook up.

I am looking forward to your install as in my case I could not make it work. I still have the Go Power TS-30 transfer switch sitting in a box on the shelf as I cold not return it.

Have fun

Keith

[acoleman43]

OK one thought that may have been overlooked. When using the Inverter you are disabling the converter which is only used when on Shore power. Do you have enough Solar and battery storage to handle the inverter power demand and how will the 12V fridge respond to low voltage situations that may result. I don't have a 12V fridge, but vaguely remember issues in low voltage situations. Just a thought - can you separate the solar and one battery from your inverter (I assume your adding battery capacity) so the fridge is not affected by inverter usage?

On thing I like about the multiplus is you can program it to shut down when battery voltage gets to a certain level, so you still have power to hook up.

I am looking forward to your install as in my case I could not make it work. I still have the Go Power TS-30 transfer switch sitting in a box on the shelf as I cold not return it.

Have fun

Keith

That's where I was going. With just 2 100AH batteries my AC alone would drain them in under 2 hours. 165W panel can't keep up with 1500W drain. But if you're using it for lights, computers, fridge and other "light" loads, a couple batteries might not be bad. I would add another matching solar panel though

[Melsman]

Hi Keith and Acoleman - Your concern about over-draining the batteries is a valid one. One of my inverter criteria is that it has a low-voltage shutdown so that it doesn't kill the batteries (or perhaps the 12v reefer). But as you correctly surmise, I ordered the trailer with additional battery capacity (two 6v deep cycle LA batteries) to accommodate the additional inverter draw (as well as the 12v reefer needs), so separating batteries is really not an option, nor should it be necessary. I don't expect to operate completely off-grid with this set-up - at least not for very long. And I certainly don't expect to run the A/C. But this system should give me enough off-grid power to do the things I wish to do (i.e. run the "light loads" mentioned) and also give me a foundation to build upon if I want to increase my off-grid abilities. (Which would include adding another solar panel.) Plus I have my portable generator.

As a note - I designed and installed a similar system in a previous motorhome that used 180 watts of PV panel and a dedicated inverter with which we dry camped frequently. However, this time around I want the inverter to power the entire AC bus, which is why I'm asking the ATS wiring question.

I still have a few more questions to answer (including some trailer wiring questions for GD), but when I build this out (and test it), I will post a separate thread describing the system build, components, and test results. (That may be a while since other projects and the approaching winter have divided my attention significantly.)

As always, I appreciate the discussion, questions, and input. I like to go through all of the "what-ifs" to make sure all of the i's are dotted.

Melsman

[sutrick2001]

I am glad I found your thread. I am in the process of attempting the same thing in my 2022 23BHE. I am adding Renogy 2000w inverter, shunt, GoPower TS 30, and 200 amps of LA batteries. Quick question, if you disconnect the converter wire from the AC breaker panel and add it to the GP TS 30 are you worried about not having a breaker to isolate the converter? I noticed on the GP TS 30 schematic it shows a fuse on the hot wire for the converter, what fuse are you using?