Victron 12/2000 Multi-plus in an Imagine?

[jh.xsnrg]

Any progress on wiring up your inverter? I'm wanting to add one in my 2800BH pass through and was wondering if you have figured out how to run AC wire from the front pass through to the breaker panel yet, and if so any pics? Many thanks and good luck with your install.

A little. I have all the parts now except the 6ga and breaker to run to the AC distribution panel. I started cutting and crimping cable, and have the DC + done and routed on the workbench.



As for running that wire once I do get it, my plan is to follow the same basic path the DC wire takes going to the DC distribution block from the battery. Everything is along the passenger side. Have to shave some gobbed foam insulation and drop the bottom plastic to run it. I am going to pull 2 sets, one to bring the shore power forward to the inverter, and one to return the 120 from the inverter.

[howson]

A little. I have all the parts now except the 6ga and breaker to run to the AC distribution panel. I started cutting and crimping cable, and have the DC + done and routed on the workbench.

Jim,
Looks like progress! Takes longer than expected, doesn't it?

Couple of questions if you don't mind: 1) In the picture the positive wiring is from:
battery > fuse > shutoff > shutoff > inverter

Any reason you chose that configuration? I had to go back and re-read my notes, since typical systems shown by AMSolar in their wiring diagrams have:
battery > fuse > shutoff > inverter

I'm sure you know mine is:
battery > shutoff > fuse > shutoff > inverter

My configuration is the result of Garret Towne's (AMSolar engineer) input in a reply to a drawing I sent him: Your drawing is pretty much accurate although I have added a switch between the inverter system’s Class-T fuse and the Lynx. If you were to add solar or alternator charging, that would happen between the Class-T fuse and the battery master switch. I eventually eliminated the Lynx Distributor but the second shutoff was left in place.

Please understand I am not claiming expertise--just commenting and comparing so you can decide for yourself if the configuration is ideal.

Finally, where are you adding the breaker? I must admit it bothers me that my inverter's output wiring (max 30A) runs halfway down the trailer, into the SmartATS, then into the c/b panel where it finally runs into the trailer's 50A main breaker. It nags at me that this is probably not ideal. I wonder if a 30A (or slightly higher?) breaker right at the inverter would be more of a fail-safe setup.

-Howard

[jh.xsnrg]

Howard,

It does, indeed, take time to do things right. I always tell my boys though, the quickest way to accomplish something is to take the right amount of time to do it once.

You are correct in your assessment of the picture. You always want the fuse to be the weakest link and protect everything you can. Those switches are marine rated and made to handle silly amounts of current, but it is still a moving device in the end. I always prefer to fuse closest to the current source, leaving the least amount of hot wire if there is a problem.

The reason I am using two switches is the one closest to the battery will be where my normal DC loads attach. This gives me a complete battery shut off of the trailer where before I had none. I will also fuse the link to the trailer by either putting a fuse inline, or just moving the auto-reset breaker from underneath. The tongue jack still has to be fed from this, so will see what makes the most sense. The second switch will be where the inverter draws DC power from. In doing it this way, I can run the trailer as it came from the factory by having the first switch on and the second one off. The one thing I need to read about again though is if when the inverter is powered down if it is a direct pass through for AC current. This only matters if I want to use shore power or generator without the inverter powered up. Mostly though, both switches will remain on.

The AC breaker will be on the line coming off the inverter feeding the camper distribution panel, again, only a couple feet from the current source. Victron recommends 6ga coming off the inverter for AC. This matches the 50A transfer switch in the inverter and allows for their assist mode. As my main in the camper is only a 30A, and will still stay in place, I will probably cap the feed to it with a 40A coming off the inverter with the 6ga. 6ga is overkill, but I won't ever have to worry about it with a 40A breaker protecting it.

The part I don't like now, is the shore power line. Truly it is no worse than before the inverter install, but I am thinking about adding a current limiting device for the shore power AC coming to the Inverter/transfer switch instead of just trusting the campground . I do have the properly sized PT-30X that will tell of problems, but it is not protected from a 50A draw if one has to use one of those dog-bones for sites that only supply 50A. In the case of a 30A trailer, the current limiting device is the breaker in your distribution panel in the RV. That is the wrong end of the line for my liking, but still far better than nothing. With the inverter in place, the 30A breaker in the trailer doesn't even do that job anymore, and the inverter sees the 50A from the campground. While the Victron is capable of this, I am not sure the wiring in the camper is up to the task. I need to check what size wiring GD puts in place for the shore power from the campground. If they want to be on the safe side for their customers, they would use 6ga even on a 30A trailer, but that would cost more too, and add a little weight.

There is a lot in the paragraph above, but basically, every leg needs to be protected against over-current vs the wire size that will supply the current, and all runs should have the least amount of unprotected conductor possible.

I am looking for a very small AC breaker box now. Something like this: http://www.midnitesolar.com/productP...tOrder=1&act=p only smaller if possible.

Jim

[G3502800]

I am looking for a very small AC breaker box now. Something like this: http://www.midnitesolar.com/productP...tOrder=1&act=p only smaller if possible.

Jim

Thanks so much for the updates, helps with my setup in progress!

For the AC disconnect right after the inverter I would suggest going to lowes or alike and asking for a mini split disconnect or alike for about $15 plus breaker. There are cheaper fused base ones too.

https://www.lowes.com/pd/Square-D-2-...Center/3457972
https://www.lowes.com/pl/Breaker-box...cal/2699721739

[howson]

The one thing I need to read about again though is if when the inverter is powered down if it is a direct pass through for AC current.

Thanks for the thoughtful and comprehensive response. Effectively mine works the same as what you have planned except I use shutoff 1 to completely isolate the batteries from everything else in the system. As shown in the diagrams posted in my thread, I hooked up the always-powered 12V devices to the INPUT side of shutoff 2 and the 6ga wire to the trailer's power distribution panel to the OUTPUT of shutoff 2 (so it acts like the OEM shutoff switch).

When on shore power, if I have my inverter off that leg is not powered in the trailer. I haven't figured out if there's a setting to "pass through" the AC. I am eager to read what you find out.

Thanks again for the update.

[jh.xsnrg]

Thanks for the thoughtful and comprehensive response. Effectively mine works the same as what you have planned except I use shutoff 1 to completely isolate the batteries from everything else in the system. As shown in the diagrams posted in my thread, I hooked up the always-powered 12V devices to the INPUT side of shutoff 2 and the 6ga wire to the trailer's power distribution panel to the OUTPUT of shutoff 2 (so it acts like the OEM shutoff switch).

When on shore power, if I have my inverter off that leg is not powered in the trailer. I haven't figured out if there's a setting to "pass through" the AC. I am eager to read what you find out.

Thanks again for the update.

It is fairly similar then. Our "always-on" stuff is connected in the same place, yours is just on the other end of the wire between the switches. I only have 1 12v lead to the camper, the single 6ga that was on the original battery, so without going further into the DC wiring of the trailer, my DC side will always have power, just like it does now. Switch one turned off will turn everything off. It sounds like yours was split into "always on" DC loads and other DC loads? Was it that way from the factory, or did you split it yourself? I think I would still want to have the ability to run all the 12v circuits without having any current from the batteries go to the inverter though, even though the inverter may be "off".

As for the AC, your experience is likely how it will work. It will probably need to be energized to pass AC from shore power. That shouldn't be a problem though, as if on shore power, may as well use it.

[howson]

It is fairly similar then. Our "always-on" stuff is connected in the same place, yours is just on the other end of the wire between the switches. I only have 1 12v lead to the camper, the single 6ga that was on the original battery, so without going further into the DC wiring of the trailer, my DC side will always have power, just like it does now. Switch one turned off will turn everything off. It sounds like yours was split into "always on" DC loads and other DC loads? Was it that way from the factory, or did you split it yourself? I think I would still want to have the ability to run all the 12v circuits without having any current from the batteries go to the inverter though, even though the inverter may be "off".

As for the AC, your experience is likely how it will work. It will probably need to be energized to pass AC from shore power. That shouldn't be a problem though, as if on shore power, may as well use it.

Jim,
The top of the first pic below shows the OEM wiring as I found it. It's a little busy but hopefully the identification of what the wires do helps. Crowded at the bottom is a system diagram.



The second pic shows how my trailer is wired now due to the removal of the OEM shutoff switch. My intention was to have it mimic the OEM's wiring. If shutoff 1 is "on" and shutoff 2 "off" the trailer is powered as if the OEM shutoff was engaged (power removed). I'm going to have to test exactly what is powered and what is not. I *think* the wire in the upper left of pic 1 (with the ?) goes to the stabilizing jack circuit, but I could be wrong.

[Country Campers]

Howard

Your "Power jack?" , actually should be for the "emergency break away switch" for the brakes. This should have power all the time.

Brian

PS. back to topic

[howson]

Howard

Your "Power jack?" , actually should be for the "emergency break away switch" for the brakes. This should have power all the time.

Brian

PS. back to topic

I know one set is for the breakaway switch and another is for the front jack. Darn it, I just messed with this the other day while troubleshooting the "no power from truck" problem but I didn't document the wires. Now I'm going to have to go look again. (I'm getting pretty darn good at crawling under my trailer without whacking my head on the a-frame!)

[jh.xsnrg]

more AC wiring.

The shore power cable on our 30A trailer is 30ft of 10 AWG. The wiring in the camper itself then is likely 10AWG all the way to the AC distribution panel's 30A breaker. This fits in the specs for 10ga wire.

As I am going to limit the AC draw with a 40A breaker from the inverter to the trailer distribution panel (shore or generator + inverter boost), a quality 8ga cable will do just fine on the run from the inverter to the distribution panel's 30A main and I can save some weight vs the 6ga I was considering. A 10ga THHN or USE-2 cable meets the 40A spec even, but I feel better about 8ga, and I am paying the bill, so over-engineering is allowed. I need to see about putting a breaker for the incoming shore power near the distribution panel. This would then feed the AC input side of the inverter and protect the run of wire to the inverter. I wonder if a small box would fit where the current DC converter is The other option would be to put the breaker in the pass-through before it goes into the inverter, but that would be trusting the breaker in the campground post more. Either location would protect against over-current through the EMS and into the Victron though.