Questions regarding "So, you want to setup a good electrical system in your camper?"

[Wallowa]

Interesting, I wonder if the vintage or dinette style dictated no venting...our '16 hawk [purchased new in Oregon] with side dinette has a small wire screened battery compartment vent on starboard side on the shelf in front corner. Same, we had FWC AGMs until I went to BB Li.


In the for what it’s worth column. In 2014 I purchased Fleet with FD with two AGM batteries. There is not a vent in the battery compartment. We lived in Oregon when we purchased it new.

 

[Utah]

I am planning a project to swap out my dual AGM batteries with a 170 AH LiFePO4 battery. While I am at it, I will add a Victron Orion DC-DC charger (12/12-30 amp) and also a 1500 watt inverter (Aims pure sine) . I have put together a wiring diagram showing the wire sizes, etc. (attached). I would appreciate any comments on the wiring diagram. Does anyone see any issues with this plan?

Also, looking for feedback on whether 4 AWG wire size is good for the inverter or whether I should go to the expense (and difficulty) of 2 AWG wire size. My current plan is to mainly use the inverter for a 600 watt water kettle. I use propane for cooktop and heater.

Thank you in advance for any comments.

 

[ntsqd]

What gauge cable do one of the various cable sizing guides call for?
My own preferred guide: https://www.ancorproducts.com/en/Resources I tend to use the 3% Voltage Drop table exclusively, but that can result in an excessively Conservative selection.

 

[Utah]

Well the Blue Sea “Circuit Wizard” calculator says that 6 AWG is adequate with inputs of 80 amps and a 10 ft circuit length. If I bump the amperage up to 125 amps then I need 4 AWG. Hope I am running the calculator correctly…

 

[Utah]

Looks like the change from 6 AWG to 4 AWG required happens at about 90 amps (per the Blue Sea calculator).

 

[Utah]

The AIMS inverter specs indicate that it is capable of 3000 watts surge. That might be over 200 amps? I assume that the 120 amp circuit breaker will trip before any hazardous condition is reached for my setup.

 

[Wallowa]

Speaking from ignorance....but why not use a 4 AWG cable if it has less resistance? Cost not a bigee, but sucking every V/A out of the system is a winning proposition....why not less resistance?

 

[Utah]

This is my thinking too. I am planning on using 4 AWG for the inverter circuit. I was wondering if I should consider 2 AWG. That seems like overkill to me.

 

[PaulT]

As the fridge is likely to be the largest energy consumer, you should evaluate its impact on the truck battery per your circuit diagram. You may want to run it off the camper battery instead. Nothing in my camper comes close to drawing down the battery as much as the fridge.

If you kill the camper battery, you can easily recharge it by the truck charging system but if you kill the truck starting battery, you will be in a tough spot.

With a dead camper battery, you can still heat water with propane. I carry a JetBoil/MSR for that purpose while sitting outdoors anyway

Paul

 

[Wallowa]

And Paul I carry this on my motorcycle trips and in the Tundra just in case the Tundra or bike starter battery goes flat...redundancy is my mantra. Light weight and compact.

"Antigravity Batteries XP-1 Micro-start Personal Power Supply & Jump Starter
DBY-ACC56-24-57 "

Phil

 

[Utah]

Thanks Paul. The fridge will indeed be supplied power from the camper battery. It is only the common negative/ground that will be connected back to the truck battery.

If you see this differently based on my wiring diagram please let me know. My understanding is that the Victron Orion will keep the truck battery isolated from the camper battery (even though there is a common ground).

 

[PaulT]

Looking at circuit diagram on my desktop with large display makes it clear. I first looked at it on my phone. Not smart with old eyes.

I saw a conclusion and jumped for it.

Paul

 

[craig333]

I can easily use my camper batteries to start the truck and before I bought new truck batteries I actually had to do that twice.

Once I gradually lost all power in the truck. I never did figure out what the cause was and it never repeated but it was sure comforting to throw the switch in the camper and bring the truck back to life especially since it was night in the middle of nowhere.

 

[Wallowa]

What switch is that?

"comforting to throw the switch in the camper and bring the truck back to life.."

 

[ntsqd]

Some isolators have the ability to be "forced" to close and connect the batteries. Other's employ a marine battery combiner switch in parallel with the isolator. I have such a system on one vehicle. A 'house battery' and a main starting battery with an Auto-Charging Relay and a battery switch between them. Can start it from either battery, or both if necessary.

 

[craig333]

I don't use an isolator, just a simple marine switch. My camper didn't come with a battery so it also didn't come with an isolator and I saw no reason to add one. It requires a bit more thought from the user though.

 

[ntsqd]

I run the cables to the battery switch, then the leads from the ACR are run to each battery's terminal on the switch. Makes the install simple and clean.

 

[Utah]

Looking into my battery compartment while I ponder the possibilities…
——-
BACKGROUND: I am replacing my old AGM batteries with new LiFePO4 battery. With this upgrade I will install a new Victron Orion DC/DC charger (here on the left wall) as well as a 1500W pure sine inverter (still thinking about where to place that).

I am NOT installing or hooking up solar panel or a solar MPPT charge controller (AT THIS TIME).
———
QUESTIONS:
(1) For future reference, is that the factory rooftop wiring shown on the right (marked “solar”)? Does this wire run directly from the rooftop plug to the battery compartment? If so, then that would be the input to an MPPT charge controller (for future consideration)?

(2) The wire on the left side is coming from the rear plug (for solar panel?) That wire appears to be running forward (to the fuse box?). If I were to hook up an external solar panel (future), why wouldn’t that connection be directly to the battery here in the battery compartment?

Thanks for any input.

 

[goinoregon]

my rear plugs, and rooftop solar uses green positive wires. apparently that is solar? from ATC

 

[Jon R]

Looking into my battery compartment while I ponder the possibilities…
——-
BACKGROUND: I am replacing my old AGM batteries with new LiFePO4 battery. With this upgrade I will install a new Victron Orion DC/DC charger (here on the left wall) as well as a 1500W pure sine inverter (still thinking about where to place that).

I am NOT installing or hooking up solar panel or a solar MPPT charge controller (AT THIS TIME).
———
QUESTIONS:
(1) For future reference, is that the factory rooftop wiring shown on the right (marked “solar”)? Does this wire run directly from the rooftop plug to the battery compartment? If so, then that would be the input to an MPPT charge controller (for future consideration)?

(2) The wire on the left side is coming from the rear plug (for solar panel?) That wire appears to be running forward (to the fuse box?). If I were to hook up an external solar panel (future), why wouldn’t that connection be directly to the battery here in the battery compartment?

Thanks for any input.
photo-output.jpeg

Not sure what camper you have.

On my 2021 Grandby FD with no factory solar components, the solar panel connector wires looked just like the ones you point to on the right side of your picture, and like yours they were coiled, capped, labeled solar, and did not have split loom over them. The wires from the roof and rear wall solar panel connectors are paralleled within the cabinet and that coiled wire pair routed to the battery compartment is connected to the paralleled connectors. If your camper is a recent FWC I suspect it’s the same. If that’s the case I have no idea what the other coiled wire with split loom is.

One of the handiest tools I ever made for electrical testing was a pair of light gage wires with alligator clips on both ends. One short, one about 12 feet long. They live in my meter case, and allow me to extend the test probes and fix them to something. With the camper battery and all truck connections disconnected, put your ohmmeter on audible beep and go exploring to see what’s connected to what!