2022 316rls

[4Mrfisherman!]

Installing a second inverter in the prep area for the second spot to run the A/C. The 12 /2 wire is a looped. Do I just cut it and hook up both ends to the inverter.? I'm using a Renogy 3000.
Thank you

[wiredgeorge]

Originally Posted by 4Mrfisherman!

Installing a second inverter in the prep area for the second spot to run the A/C. The 12 /2 wire is a looped. Do I just cut it and hook up both ends to the inverter.? I'm using a Renogy 3000.
Thank you

This is hard to follow. Is your 2nd A/C a 12VDC unit? Not sure I have heard of such. Most use 120VAC. Not sure how a Renology 3000 or inverter fit in; perhaps some additional explanation is in order. Thanks

[4Mrfisherman!]

My trailer came pre wired to install an inverter(second)
To run my main cabin Coleman mach q air conditioner when not plugged into shore power . The air conditioner runs on 110 a/c when on shore power.

[NH_Bulldog]

Before you go that route, have you looked into the practical reality of running an AC off batteries? First, you need a soft-starter on the AC, and then you need a fairly massive amount of battery reserve capacity to run a 15k AC for more than 30-60 minutes (which will take you down to a 0% state of charge on 200ah of lithium batteries), then you need a way to replenish the batteries once depleted (don’t count on solar for this). The inverter loop prep is only a small part of the AC inverter requirements. You also need very substantial wiring from the batteries to the inverter to power the inverter and anything running off the inverter.

How much solar panel capacity do you have on the roof? How many batteries, what type, and what is their total combined AH capacity? Do you have a generator to quickly recharge if solar panel capacity is limited? Don't forget to consider all the other loads on the system besides the AC (converter/charger refrigerator, lights, TV, etc).

You may very well have thought of all of this (hopefully you didn't rely on the marketing hype that implies it is plug and play), but we really do need some additional details before we can provide any meaningful assistance to your original question.

[4Mrfisherman!]

Thank you for asking
The Air Conditioner is the only thing on that circuit.
The system is built with 3 100ah batteries parallel. It has 900 watts of solar on top. It has 2/0 600 amp welding cables for battery to inverter leads.It has a victron 50 amp solar charger controller.
When I removed the prep cover for this additional system the rolmax was a single continues wire. I now realize it is because it needs to be a pass through situation. When there's shore power it works and when we're not hooked up to shore power the inverter is used to power that circuit.

[JRTJH]

Also, have you considered that 12/2 ROMEX is rated at 20 amps. A 3000 watt inverter produces 25 amps. Using that inverter, in addition to the MASSIVE 12 volt input cables you'll need, can produce an unsafe overload of the trailer's ROMEX wiring. Burned or hot ROMEX in the walls is not a "good thing" when you're using that system "at a remote rest area or in an unimproved campground" located miles from the closest fire department.

[NH_Bulldog]

Originally Posted by 4Mrfisherman!

Thank you for asking
The Air Conditioner is the only thing on that circuit.
The system is built with 3 100ah batteries parallel. It has 900 watts of solar on top. It has 2/0 600 amp welding cables for battery to inverter leads.It has a victron 50 amp solar charger controller.
When I removed the prep cover for this additional system the rolmax was a single continues wire. I now realize it is because it needs to be a pass through situation. When there's shore power it works and when we're not hooked up to shore power the inverter is used to power that circuit.

My comment on the other loads was in regard to all of the power loads in the camper, 12v DC or 120v AC. When not connected to shore power, 100% of your power is coming from the batteries either as a 12v DC draw, or 120v AC through the inverters. All of those loads combined will need to be considered in how much power the system will consume and how long you can realistically expect to keep the lights on.

300ah of battery and 900w of solar will still only get you so far. One cloudy day using the AC on the inverter and your system will not generate enough power to recharge the batteries. Two cloudy days and you may not have enough to run the jacks or move the slides if you want to leave. Three cloudy days and you may not have enough to keep the lights on or the refrigerator operating. The fact is that even with that setup, you are drawing more power from the system than the system can generate, so you will deplete the batteries. This is why you need to include a generator in this equation. The solar panels do not output 900w of energy, even under "perfect" conditions (which seldom if ever exist in the real world). Remember that panel ratings are determined in a tightly controlled testing environment that is impossible to replicate out in the field.

All that aside, to answer your question regarding the AC inverter loop prep; yes, that 12ga loop of Romex feeds the rooftop AC unit. With all power disconnected, you cut that loop and then re-energize the circuit and note which end of the loop is the line (supply) and which is the load. Turn the power back off. The line end goes to the inverter "in" and the load end goes to the inverter "out". Lastly, as noted previously, you also still need a soft-start on the rooftop AC unit.

[4Mrfisherman!]

Thank you for your feedback. It is greatly appreciated