Backfeed RV electrical panel w/inverter?

[Ntrinh15]

So im looking to take a trip in April and dont want to run the generator the whole trip while driving. I want to buy a inverter to backfeed the panel on a separate breaker.

So there is 2 legs on the panel 50amp each leg. Run a 30 amp breaker on the line and run this to my inverter. When the rig is driving I want to be able to run the TV and outlets. So when I shut off the main breaker and turn on the inverter it powers up every other breaker off the inverter. I would rewire the wires off to make this happen at the panel.

Now I want to know if the alternator will still charge the house batteries off the alternator while driving?

I know they make transfer switches and units that make this all automatic. However a huge price difference from buying a 3000w inverter to a Victron multiplus to run everything.

Hope all this made sense

[lwmcguir]

Originally Posted by Ntrinh15

So im looking to take a trip in April and dont want to run the generator the whole trip while driving. I want to buy a inverter to backfeed the panel on a separate breaker.

So there is 2 legs on the panel 50amp each leg. Run a 30 amp breaker on the line and run this to my inverter. When the rig is driving I want to be able to run the TV and outlets. So when I shut off the main breaker and turn on the inverter it powers up every other breaker off the inverter. I would rewire the wires off to make this happen at the panel.

Now I want to know if the alternator will still charge the house batteries off the alternator while driving?

I know they make transfer switches and units that make this all automatic. However a huge price difference from buying a 3000w inverter to a Victron multiplus to run everything.

Hope all this made sense

That is doable but the downside is the lack of EMS

EMS are in all higher end coaches and RV's to avoid overloading inverters and the resultant issues

[DavidEM]

It is doable, but extremely risky.

With both an inverter and shore power wired to the same leg, you run the risk of frying your inverter if both the inverter and shore power are on at the same time. Two sources of power connected together do not like it unless it is a special inverter with AC boost capabilities.

The other risk is that you forget, turn on some high current load, like a microwave, A/C unit, etc and either trip the inverter's DC breaker, overload the inverter itself or run down your batteries unknowingly.

I would only install an inverter with a built in transfer switch in this situation. It is also possible to isolate the AC buss so that only certain breakers can be powered from the inverter. Read the attached article for how to do it. It was written for boats, but applies equally to RVs.

David

[Ntrinh15]

I know I could run the inverter and run it to an outlet or extension cords. Im just trying to keep it clean looking and dont want anyone tripping over wires. If I had shore power i would not have the breaker or inverter on. I would only use it when i dont have shore power. Ultimately we are back feeding our rigs when we hook up the 50 amp service on shore.

[lwmcguir]

120v should pass through the inverter

I can leave mine on when operating the generator or on shore power and everything works fine

[Ntrinh15]

Originally Posted by lwmcguir

120v should pass through the inverter

I can leave mine on when operating the generator or on shore power and everything works fine

What kind of inverter do you have?

And are you driving when you have your inverter on?

I dont know how much boon docking Ill be doing. I mainly want the inverter to power the tv and outlets to charge phones and laptops. It would be nice for the fridge to be on as well while driving so i dont have to use the generator.

[Beau388]

If you are going to keep the coach for a while why not install the inverter correctly. The better and more expensive inverters allow complete remote control. Although my coach came with a Xantrex Pro 1000 I replaced it with a Xantrex Freedom Xi 2000. My coach is a Thor MC Plant 750 like yours so the wiring should be similar. All the wiring to be moved is under the bed so that is the logical place to install the inverter. Running the cable to the remote will be a problem as you probably do not have a wiring chase from the bed to the hall control center. I use a cheap sub panel to tie-in all circuits but the GFCI to the 30 amp pass through circuits. The only new wiring was from a 30 amp CB to the inverter and from the inverter to the sub panel. Of course I had to double the cable from the batteries to the inverter to handle the 250 amps. Hope the pictures help.

[Ntrinh15]

Originally Posted by Beau388

If you are going to keep the coach for a while why not install the inverter correctly. The better and more expensive inverters allow complete remote control. Although my coach came with a Xantrex Pro 1000 I replaced it with a Xantrex Freedom Xi 2000. My coach is a Thor MC Plant 750 like yours so the wiring should be similar. All the wiring to be moved is under the bed so that is the logical place to install the inverter. Running the cable to the remote will be a problem as you probably do not have a wiring chase from the bed to the hall control center. I use a cheap sub panel to tie-in all circuits but the GFCI to the 30 amp pass through circuits. The only new wiring was from a 30 amp CB to the inverter and from the inverter to the sub panel. Of course I had to double the cable from the batteries to the inverter to handle the 250 amps. Hope the pictures help.

Yes the pictures always help. So I dont know if I have an inverter already. I need to get the wiring schematic for this coach. If we didnt just get a foot of snow here I would be opening the bed to take a look under it and see whats going on. Im just trying to get as much info and want to start buying some of the things needed instead of waiting the last second.

Ive seen some of the coachs have a 12v disable feature on some of the electronics. So when the key is in the ignition it sends a 12v signal to block power to tv and dvd outlets.

[Beau388]

Originally Posted by Ntrinh15

Yes the pictures always help. So I dont know if I have an inverter already. I need to get the wiring schematic for this coach. If we didnt just get a foot of snow here I would be opening the bed to take a look under it and see whats going on. Im just trying to get as much info and want to start buying some of the things needed instead of waiting the last second.

Ive seen some of the coaches have a 12v disable feature on some of the electronics. So when the key is in the ignition it sends a 12v signal to block power to tv and dvd outlets.

Thor MC Plant 750 coaches had the inverter optional on coaches over 31 ft. They were standard on any plant 750 coach with an outside kitchen in order to power the 120 volt fridge or on a coach with a 120 volt interior fridge.
Old DOT reg that there can not be a video display device within eye sight of the vehicle's driver, operative when the parking brake is OFF. Recently this reg has been modified to exempt rear view camera display with the vehicle in reverse. The latest change is to not restrict the rear view camera display in any way.

[Ntrinh15]

Originally Posted by Beau388

Thor MC Plant 750 coaches had the inverter optional on coaches over 31 ft. They were standard on any plant 750 coach with an outside kitchen in order to power the 120 volt fridge or on a coach with a 120 volt interior fridge.
Old DOT reg that there can not be a video display device within eye sight of the vehicle's driver, operative when the parking brake is OFF. Recently this reg has been modified to exempt rear view camera display with the vehicle in reverse. The latest change is to not restrict the rear view camera display in any way.

I meant the tvs in the back. I have enough to worry about driving I dont need another distraction. I really just looking to power the MH while driving without running the generator.

[Beau388]

Originally Posted by Ntrinh15

I meant the tvs in the back. I have enough to worry about driving I dont need another distraction. I really just looking to power the MH while driving without running the generator.

There are all sorts of things inverters can do rather than replace a generator. Mine comes on anytime the is power to the power center. It provides a UPS for the coach's 120 circuits of if I lose shore power, it picks up the load so DirecTV does not reboot and my NAS doesn't die. It lets me set the low voltage cutout, monitor input and output voltages, amperages, etc. There are inverters that can supplement shore power when the voltage gets low. Small full function inverters usually have a 15 amp pass-through relay; medium size inverters have a 30 amp pass-through relay and the big inverters have a 50 amp pass through relay. There are even split phase inverters that can power both sides of a 50 amp coach with dual 30 amp pass-through relays. Just don't buy to much inverter for your house battery bank. I would recommend 200 amp-h usable for each 1,000 watts of inverter capacity, but there are other recommendations. Have fun; that's what RVing is all about.

[dkoldman]

I wanted to do the exact same thing but somehow it was a lot simpler than what I think I am reading you want to do...

I may be missing something, specifically are you saying your 33' RV did not come with a Inverter?

If it didn't; my focal point would be 100% on getting a 2000 watt Inverter, don't know how you live without.

My RV came with 1000W Inverter. Never tripped a breaker but the Fridge was NOT wired to it. So what I did was simply a heavy duty appliance wire/cord from a Inverter supplied receptacle to create a new female receptacle to plug my fridge into. So now, whenever I drive my Inverter is always on and fridge stays on electric. The Alternator keeps my batteries over 13volts.

FWIW; I only have 1000w and I have never tripped the breaker, but if I were to buy one or replace mine; I would get 2000w. My RV was wired assuming that I had a larger inverter so it is easy swap, but no need for me unless this current one fails.

[16ACE27]

Originally Posted by Ntrinh15

What kind of inverter do you have?

And are you driving when you have your inverter on?

I dont know how much boon docking Ill be doing. I mainly want the inverter to power the tv and outlets to charge phones and laptops. It would be nice for the fridge to be on as well while driving so i dont have to use the generator.

What kind of fridge do you have? If it is residential (120 VAC only) then you already have an inverter. If you have a factory inverter it already powers the TVs and fridge and select outlets.

If you have an absorption fridge that runs off either propane or 120 VAC then you are starting from scratch without an inverter.

First obstacle: does your alternator charge your house batteries? If everything is working correctly as designed in your coach the answer is yes.

Second obstacle - inverter powered circuit using ATS. You should easily be able to find a quality 3000 watt inverter with an integral ATS. Forget wiring the inverter to your current power center. Have the breakers in the power center that supply your TV and fridge be the input to the inverter's ATS. There should be one breaker for the TVs and select outlets and a different circuit for the fridge. That's how most inverter installs are done and it makes inverter operations thoughtless as long as the inverter is turned on.

[Ntrinh15]

Originally Posted by 16ACE27

What kind of fridge do you have? If it is residential (120 VAC only) then you already have an inverter. If you have a factory inverter it already powers the TVs and fridge and select outlets.

If you have an absorption fridge that runs off either propane or 120 VAC then you are starting from scratch without an inverter.

First obstacle: does your alternator charge your house batteries? If everything is working correctly as designed in your coach the answer is yes.

Second obstacle - inverter powered circuit using ATS. You should easily be able to find a quality 3000 watt inverter with an integral ATS. Forget wiring the inverter to your current power center. Have the breakers in the power center that supply your TV and fridge be the input to the inverter's ATS. There should be one breaker for the TVs and select outlets and a different circuit for the fridge. That's how most inverter installs are done and it makes inverter operations thoughtless as long as the inverter is turned on.

I have a fridge that runs on power and propane. So probably dont have a inverter.

Do you have a wiring diagram for this? I would like to do this to make it easier on the road.

[16ACE27]

Originally Posted by Ntrinh15

I have a fridge that runs on power and propane. So probably dont have a inverter.

Do you have a wiring diagram for this? I would like to do this to make it easier on the road.

A wiring diagram would be specific to your coach showing actual wire connections, so no, I don't have that. But a schematic showing electrical connections is pretty easy to come up with.

[Ntrinh15]

Originally Posted by 16ACE27

A wiring diagram would be specific to your coach showing actual wire connections, so no, I don't have that. But a schematic showing electrical connections is pretty easy to come up with.

I have to get one. Does thor offer it off there website?

[gnach]

Originally Posted by Ntrinh15

I have to get one. Does thor offer it off there website?

Sign up to get the Owner's Resource at
https://www.thormotorcoach.com/owners/
You will need your VIN (last 8) to register. Then look at the Document Center, drop down Document Type, Schmatics PDF. Download and/or print any or all (suggested) pages. These are considered shop drawings not as-built, so your mileage may vary <wink>. Good luck.

[lwmcguir]

Originally Posted by Ntrinh15

What kind of inverter do you have?

And are you driving when you have your inverter on?

I dont know how much boon docking Ill be doing. I mainly want the inverter to power the tv and outlets to charge phones and laptops. It would be nice for the fridge to be on as well while driving so i dont have to use the generator.

Magnum and yes when driving the inverter powers the Fridge

Also make coffee and use the microwave when stopped without the generator

[Chief2650]

I had to consider this as well. The simple solution was to wire a 30 Amp plug up to the inverter and put it in the cord compartment. Now I just plug the shore power into the inverter. You do have to remember one thing which is to turn off the converter that charges the battery. It's a 110 breaker in the panel marked converter. This converts the 110 to 12v dc for charging the batteries. If you don't do this your batteriies will be trying to charge themselves. I don't know what problems this could cause. But it will drain your batteries quickly at the very least if you don't shut it off. You would need to do this if you ran it through the panel as well.

[Thorfreedom]

Originally Posted by Ntrinh15

So im looking to take a trip in April and dont want to run the generator the whole trip while driving. I want to buy a inverter to backfeed the panel on a separate breaker.

So there is 2 legs on the panel 50amp each leg. Run a 30 amp breaker on the line and run this to my inverter. When the rig is driving I want to be able to run the TV and outlets. So when I shut off the main breaker and turn on the inverter it powers up every other breaker off the inverter. I would rewire the wires off to make this happen at the panel.

Now I want to know if the alternator will still charge the house batteries off the alternator while driving?

I know they make transfer switches and units that make this all automatic. However a huge price difference from buying a 3000w inverter to a Victron multiplus to run everything.

Hope all this made sense

I installed 2000watt inverter directly to house batteries. I ran one wire from my inverter to near my rv main power wire. We plug our rv main wire in the inverter and bring all our outlets on while driving. Only thing is to cut your converter breaker off. For that i installed a relay between converter and electical panel. Now when i turn inverter on converter goes off automatically. we did two cross country trips with this set up and it has worked good. When we drive our reffegerator also works on inverter. May be this helps. happy camping.