2021 Thor Four Winds: Tracing the Inverter output

aloks

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Hello, Am looking to feed the inverter output to one of the receptacles that works on shorepower / generator only. This will allow us to power our laptop + monitor while boondocking. The surface laptop dock requirement is for 200W and was hoping to provide AC so to not mess with the laptop brick.

The rig has a 3KW renogy inverter that supplies power directly to the TV receptacle. How best can I route a 14AWG romex from the TV outlet to the dinette area so that it's not noticeable? Attaching a floorplan to better understand my rig. If this can be done easily then I can remove the existing connection to the dinette receptacle and feed it off the inverter only.

Thanks in advance!
 

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Where is the inverter located? Reason I'm asking is your TV receptacle is probably in the cabinet over the entry door, and it may be simpler to use another approach... provided the inverter is reasonably close to the power center (fuses/breaker box).
 
Where is the inverter located? Reason I'm asking is your TV receptacle is probably in the cabinet over the entry door, and it may be simpler to use another approach... provided the inverter is reasonably close to the power center (fuses/breaker box).
Thanks for responding! The inverter is located in the storage area below the bed. I checked the bottom of the bed and it is closed off. The power center is at the base of the bed and there is just enough of a hole cut for the existing wires to go through. Yes, the TV outlet is in the cabinet next to the entry above the chair
 
3000 watts is not a standard OEM Thor inverter.
What Year/Make/Model RV do you have?
What type of refrigerator?
What Make/Model inverter?

Most Thor OEM inverter installs have a built-in Automatic Transfer Switch (ATS) that allows SP to feed residential fridges and TV circuits, but switches to the inverter output when not on SP and the generator is not running. We don't know if your inverter install follows that convention or if it is a completely aftermarket install.

You should be able to remove the panel under the bed for access to the back of the Power Center, inverter, and other under bed wiring.

The easiest way to traditionally do what you want is to find the inverter output and find the 120 VAC circuit that supplies the receptacle that you want to be inverter powered and move that entire circuit to the inverter.

So let's find out what you have and then we can advise you better from there.
 
3000 watts is not a standard OEM Thor inverter.
What Year/Make/Model RV do you have?
What type of refrigerator?
What Make/Model inverter?

Most Thor OEM inverter installs have a built-in Automatic Transfer Switch (ATS) that allows SP to feed residential fridges and TV circuits, but switches to the inverter output when not on SP and the generator is not running. We don't know if your inverter install follows that convention or if it is a completely aftermarket install.

You should be able to remove the panel under the bed for access to the back of the Power Center, inverter, and other under bed wiring.

The easiest way to traditionally do what you want is to find the inverter output and find the 120 VAC circuit that supplies the receptacle that you want to be inverter powered and move that entire circuit to the inverter.

So let's find out what you have and then we can advise you better from there.
Thanks for the details! It's a 2021 Thor Four Winds 23U. When I bought; it had a 1KW Renogy which I updated to a 3KW (Renogy). The inverter does have a ATS but it's not in use and the SP / Generator output via a transfer switch is fed directly to the breakers. The earlier wiring wasn't utilizing the inverter ATS so I didn't wire anything additional before I understood how things are.
 
ACE beat me to it. That's EXACTLY what I was thinking. Honestly with a 3k inverter you could power your entire motorhome EXCEPT the A/C. BUT... without pass through feature on the inverter, you're limited to battery power with no easy option of shore power.

Simplest is to do as ACE said... find the circuit with the outlet you want under the dinette and isolate that to the inverter. It likely will have other outlets, so be aware of that. Just make sure you're aware of EVERYTHING on that particular circuit because you'll be running strictly off battery. Some appliances are also plugged into outlets (microwave). Just a heads up.

For reference I have a 3k inverter/charger with integrated transfer switch (pass through), so I wired it to power the entire motorhome. That's REALLY convenient... I love it because there's no thinking about what's available and what isn't... everything just works. BUT... we never run A/C off the inverter... no soft start.

If you have the capability I would recommend doing it that way... sounds like your equipment will support that. As for what you're trying to accomplish, wiring the entire panel might be easier than trying to isolate a single circuit.
 
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That is the eventual goal. I still need to get another battery - right now it's a 300AH LiFePO4. I did order a new ATS and was planning to hook the input of the Inverter and the SP + Generator to this new ATS and feed the output to the breaker panel. That to me is the cleanest solution but the way everything is closed off makes me a bit nervous to poke around and do something that eventually ends up being more of a headache than a feature :):)
 
Thanks for the details! It's a 2021 Thor Four Winds 23U. When I bought; it had a 1KW Renogy which I updated to a 3KW (Renogy). The inverter does have a ATS but it's not in use and the SP / Generator output via a transfer switch is fed directly to the breakers. The earlier wiring wasn't utilizing the inverter ATS so I didn't wire anything additional before I understood how things are.
So how is the inverter currently feeding the TV circuit?
And you don't have a residential fridge?
And why would you need another ATS in the inverter already has one? Unless it's not rated for 30 amps.
 
Attaching a crude diagram of the wires I have been able to trace till now. I do not have a residential fridge. It's a SP / Generator / LPG fed dometic fridge. The only other electrical appliance is a microwave and an AC.

I believe the inverter is currently directly feeding the TV receptacle. That's the only point I have found that works when the inverter is on (turns off when Inverter is not On) and isn't affected by SP connected or not.

The only reason I was thinking of another ATS was to connect it to the Inverter and the existing ATS output before sending it to the breaker panel. That way I wouldn't have to touch the existing input of the SP and Generator.

Looking at the floor plan I attached in the original post; the SP and Generator are both combined inside the dinette seating. The wires are going below the fridge and possibly through the bathroom into the breaker panel that is located at the base of the bed. The inverter though is in the storage area beneath the bed and all the wires are snaked behind walls / underneath the floor.
 

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Looking at your diagram... IF your inverter has "pass through", which is essentially a built-in transfer switch, all you need to do is re-wire the inverter between the existing ATS and breaker panel... no extra ATS needed.

Caveat... doing this will usually require the inverter to be turned ON while on shore power. Very important to check the inverter specs and installation manual.
 
Attaching a crude diagram of the wires I have been able to trace till now. I do not have a residential fridge. It's a SP / Generator / LPG fed dometic fridge. The only other electrical appliance is a microwave and an AC.

I believe the inverter is currently directly feeding the TV receptacle. That's the only point I have found that works when the inverter is on (turns off when Inverter is not On) and isn't affected by SP connected or not.

The only reason I was thinking of another ATS was to connect it to the Inverter and the existing ATS output before sending it to the breaker panel. That way I wouldn't have to touch the existing input of the SP and Generator.

Looking at the floor plan I attached in the original post; the SP and Generator are both combined inside the dinette seating. The wires are going below the fridge and possibly through the bathroom into the breaker panel that is located at the base of the bed. The inverter though is in the storage area beneath the bed and all the wires are snaked behind walls / underneath the floor.
Let me rephrase my question:

Is there a cord plugged into the inverter's output receptacle?
Or is there a romex cable hard wired into the inverter's output?
 
Just use long enough 10/2 NMS cable (Romex) to reach each component. The first connection is inside the ATS. Then a cable to the inverter input. Then a cable from the inverter output to the breaker box (power center). It's certainly okay to use lever nuts inside the ATS and breaker box. You shouldn't need any other splices... but if you do, they should ALWAYS be enclosed in a junction box... preferably metal.
 
It's a 12/2 romex hard wired to the inverter's output
OK, so in summary:
You had a non-OEM inverter installed to power only the TV circuit ONLY from the batteries.
You upgraded the original inverter to a Whole RV Capable inverter, but didn't change any wiring.
You asked us how to power a single receptacle from the inverter for your laptop needs.
The thread has veered off course to powering the entire RV from the inverter.

If I were you AT THIS POINT I would get under the RV and verify the ability to route a wire from under the dream dinette to under the bed. Thor usually runs cables under the RV instead of through interior walls.
Then install a new "inverter powered" receptacle under the dinette and run a 14-2 Romex under the RV back to the inverter and put a plug on it and plug it into the inverter.
Mission accomplished.


Then, start your plan to do the whole RV install. This may include:
Changing the inverter's battery cables - they probably are not sized to handle the full 3000 watt load.
Maybe moving the inverter closer to the battery.
Running two 10-2 Romex cables between the SP input and the Inverter output and utilizing the built-in ATS and UPS capabilities.
Upgrading your LFP battery bank.
Installing an "easy ON/OFF" switch to turn off the converter/charger when the inverter is supplying the RV.

Good Luck
 
I would hope that when OP installed that 3k inverter the battery cable length and gauge were considered and upgraded if necessary??

I'm betting the 120v cable in this class C motorhome are NOT ran through the floor... they weren't in mine. The cable to the dinette outlet probably was ran under the shower, then under the toilet riser, through the bottom of the closet to an outlet in the rear dinette seat box. (See post #9)

SInce the inverter is under the bed, EASY would be to just identify that receptacle Romex, disconnect it from the breaker panel, then connect it to the inverter output - which has the TV outlet connected. DONE.

Now... If you DO ever want the "whole house inverter" setup, the battery cables MUST be rated and fused for the 3,000 watt inverter, EVEN if you don't use it's full capacity. You won't - unless you try running your A/C.

I have essentially what you have... 300Ah of battery and a 3k inverter. For starters, 300Ah of battery is woefully inadequate for air conditioning... but it will run everything else for many many hours.
 
Thank you both @Chateau_Nomad, @16ACE27 for the inputs! I have an action plan for the short term and long term and appreciate both your ideas!

Regd the battery cable rightsizing - I have not changed it yet since I just replaced 1KW with 3KW inverter. As I look to rerouting the breaker panel to source off the inverter I will look at the cable sizing and change if needed.

The cabling is indeed inside as @Chateau_Nomad mentioned and not from below.
 
I would hope that when OP installed that 3k inverter the battery cable length and gauge were considered and upgraded if necessary??

I'm betting the 120v cable in this class C motorhome are NOT ran through the floor... they weren't in mine. The cable to the dinette outlet probably was ran under the shower, then under the toilet riser, through the bottom of the closet to an outlet in the rear dinette seat box. (See post #9)

SInce the inverter is under the bed, EASY would be to just identify that receptacle Romex, disconnect it from the breaker panel, then connect it to the inverter output - which has the TV outlet connected. DONE.

Now... If you DO ever want the "whole house inverter" setup, the battery cables MUST be rated and fused for the 3,000 watt inverter, EVEN if you don't use it's full capacity. You won't - unless you try running your A/C.

I have essentially what you have... 300Ah of battery and a 3k inverter. For starters, 300Ah of battery is woefully inadequate for air conditioning... but it will run everything else for many many hours.
So I took a quick look and removed some paneling and am able to get access to the back of the breaker panel from the Inverter. For the short term I was thinking of disconnecting the dinette receptacle from the breaker panel; attach a 3 pin plug and tie it to the inverter AC output using a https://a.co/d/9zaFLjI. The dinette cable is not long enough to reach the inverter and so the plug will allow me to use the Amazon cord as an extension. The inverter has 3 AC outlets in addition to the romex outlet so thinking to utilize one of them.
 
So I took a quick look and removed some paneling and am able to get access to the back of the breaker panel from the Inverter. For the short term I was thinking of disconnecting the dinette receptacle from the breaker panel; attach a 3 pin plug and tie it to the inverter AC output using a Amazon.com. The dinette cable is not long enough to reach the inverter and so the plug will allow me to use the Amazon cord as an extension. The inverter has 3 AC outlets in addition to the romex outlet so thinking to utilize one of them.
Sounds like a plan! :thumb:
 

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