Solar + Batteries + Inverter + Converter

[wandered]

Hi, I'm renovating the power system for boondocking. The attached drawing shows the depth of my thinking. My questions are around tying in an inverter (which I have not purchased; all other items on drawing are purchased).

The inverters I'm looking at have two outlets built in and a way to hook in some Romex (10/2 for example). I want to hook that into the existing distribution panel but have some questions:

1. instructions suggest a fuse between battery and solar controller. Do I also need to insert a fuse(s) between inverter and battery?

2. Should I wire the inverter output directly to the same terminals shore power terminates in the distribution panel? Will this allow all downstream 110 components to work from inverter?

3. What can I add so the inverter knows to auto switch itself off when shore power is detected?

Thanks for any thoughts -- nothing (that wasn't already there) is screwed down yet so feel free to suggest anything [emoji1]

Ed

[wandered]

Ignore the colors... They didn't stay consistent.

[DaveP]

I bought (and would buy again) a hybrid inverter/charger form Victron or Magnum (I did Magnum) then you do not have to worry about it.

"2. Should I wire the inverter output directly to the same terminals shore power terminates in the distribution panel? Will this allow all downstream 110 components to work from inverter?

3. What can I add so the inverter knows to auto switch itself off when shore power is detected? "

[daleyocum]

Originally Posted by DaveP

I bought (and would buy again) a hybrid inverter/charger form Victron or Magnum (I did Magnum) then you do not have to worry about it.

"2. Should I wire the inverter output directly to the same terminals shore power terminates in the distribution panel? Will this allow all downstream 110 components to work from inverter?

3. What can I add so the inverter knows to auto switch itself off when shore power is detected? "

You’ll find many folks on this forum will agree with this advice. I’ve had the Magnum hybrid inverter in the past and have the Victron Multiplus now. Both are great and makes it possible to easily make every outlet in your trailer hot while on battery, generator, or shore power. The Victron is cheaper than Magnum and is part of a whole ecosystem should you decide to add solar.

[Shermy1987]

If you dont want to go the inverter/charger route, you just add a transfer switch such as this

https://www.amazon.com/PowerMax-PMTS...71924699&psc=1

[daleyocum]

Also, on your diagram you have a series connected pair of 6v batteries in parallel with a couple of 12v batteries. Not a good idea. When you put 12v batteries in parallel you want them all to be the same age and model and thus have the same charging profile. Otherwise one battery will end up discharging trying to “charge” another. Also your solar charge controller, at least an efficient one like a Victron MPPT controller, won’t know what’s going on and won’t be able to step through its stages accurately.

Your life will be much simpler with an all-Victron system and matched batteries. There are lots of resources on this forum.

[wandered]

Appreciate that -- was completely wondering about my battery configuration... Ended up with the mismatch and was curious if I could use them together.

If I'm stuck with them, maybe I'll just put a manual switch in and keep the batteries separate.

[gklott]

Originally Posted by wandered

1. instructions suggest a fuse between battery and solar controller. Do I also need to insert a fuse(s) between inverter and battery?

Yes, required for both. Recommend using BlueSea Series 187 circuit breakers. See ANSI/RVIA Low Voltage standard 2018 ed. for details.

Originally Posted by wandered

2. Should I wire the inverter output directly to the same terminals shore power terminates in the distribution panel? Will this allow all downstream 110 components to work from inverter?

No. You must use a transfer switch, as you have separately derived power sources. Some inverters include an automatic transfer switch for this purpose. The are other good transfer switches for RV use. Recommend consulting the several sections of the National Electric Code that cover this. Ensure that the transfer switch is UL or ETL listed.

Originally Posted by wandered

3. What can I add so the inverter knows to auto switch itself off when shore power is detected?

Again, some inverters have this capability with the automatic transfer switch.

73/gus

[gklott]

Originally Posted by daleyocum

Also, on your diagram you have a series connected pair of 6v batteries in parallel with a couple of 12v batteries. Not a good idea.

Agree. This is not a good idea.

Originally Posted by daleyocum

Your life will be much simpler with an all-Victron system and matched batteries. There are lots of resources on this forum.

Agree. Matching battery types is important unless your charger provides multiple outputs, each capable of providing a different charging profile, and where each battery bank supplies a separate DC load buss.

73/gus

[lyleapgmc]

You don't need a fuse anywhere until you need it. Fuses are to protect the wires. If a unit fails you most definitely want a fuse to blow. Don't cheap out on the fuses. Fuse everything. Fuses and holders are cheap. A fire caused by a burning wire is not so cheap.

[wandered]

Originally Posted by lyleapgmc

You don't need a fuse anywhere until you need it. Fuses are to protect the wires. If a unit fails you most definitely want a fuse to blow. Don't cheap out on the fuses. Fuse everything. Fuses and holders are cheap. A fire caused by a burning wire is not so cheap.

Great advice! So obvious now that I'm reading and hearing it.

[Fair_Enough]

W,
Attaching a simplified schematic of what I have to possibly give you ideas.
I had never seen this done, but I pulled out the 30A distribution panel and replaced with a 50A, so I could have an integrated sub panel in the main panel. I had the panel left over from a project I did a different way. I think you will notice the exact layout of the power center turned out a bit different, since I repurposed all I could.

I used a progressive auto transfer switch with the inverter controlling... ie, when the inverter is on the feed from shore power to the subpanel is disconnected... and the inverter supplies... turn off the inverter and it cuts shore back through automatically.

I also found a cool 300A fuse and terminal that fits directly onto the battery and added a battery cut off on the battery box.

I used Trimetric SC2030 and TM2030 equipment, which I know... its old school PWM, but highly programmable.

I took a chance with a $300 PSW inverter and it has worked perfectly. Actually surprising me. I had a Magnum ($1500) in the toyhauler and no doubt they are incredible. If I was going Magnum, I would use its built in charger (again, highly programmable) and not bother with the PD4655VL upgrade. I normally keep the converter turned off. I also have the remote that lets me force the converter into boost if I ever need to and have shore power or generator power.

Like was well covered, you "can't" mix battery types or even those with a born on date much different. They don't play well together.

Let me know if I can help.
Clint

[gator.bigfoot]

Originally Posted by lyleapgmc

You don't need a fuse anywhere until you need it. Fuses are to protect the wires. If a unit fails you most definitely want a fuse to blow. Don't cheap out on the fuses. Fuse everything. Fuses and holders are cheap. A fire caused by a burning wire is not so cheap.

As long as the fuse is sized correctly to protect the wire. Otherwise it doesn't do a whole lot of good.

[waninae39]

THIS IS OUR SCHEMATIC FOR AC AND dc

MOSTLY vICTRON DEVISE AS THEY ALL TALK TO EACH OTHER

PLUS victron supports free online monitoring

listen to the others about battery, wiring and fuses

[wandered]

Wolfwhistle and waninae39 thank you for sharing your schematics. Very helpful and impressive.

What do the shunts do for you? Is it just a place to measure or do they restrict current above their rating for safety?

[TouringDan]

Want to follow along so I can learn and improve my setup.

Dan

[waninae39]

shunts allow accurate measurements. they are VERY low resistance

std device in any electrical system when you need to know.

[Fair_Enough]

Yes, a shunt is a precision device at a exact resistance. The kelvin connections allow a precision meter to read the voltage drop that it converts to amps. A 100 amp model for loads (think inverter up 600 W) and 500 amp for larger DC loads. Even though the big one is 500 amps, you should not expect to put that high a current thru it continuously. It will heat up and give incorrect readings. I think 300A or so is okay. I have the data sheet for the one Trimetric uses but don’t remember the finer points. I would never be without a monitor whether trimetric or Victron. Notice in the schematic all negative loads flow thru it. If a negative is connected to the battery that current used is no measured.
Clint

[napabill]

I think the battery fuse Wolfwhistle used is the same one I like: https://www.amazon.com/gp/product/B0...e?ie=UTF8&th=1