DCDC charger upgrade / winter project

[Bcubed]

I have upgraded my truck from a 2014 Tacoma to a 2024 Tundra, and am running a 2012 FWC Fleet. Have upgraded the battery to 100AH lithium and am running 200 watts of solar. I only run the internal electronics on the battery (lights, pump, etc), and use propane for the fridge.

Since upgrading to the Tundra, we haven’t done any longer trips, and the 100AH plus solar has been plenty, so haven’t bothered doing any wiring from the truck battery, understanding that the truck has a smart alternator and therefore the camper woukd require a DCDC charger, and not just a simple wire that (like the one I had on my Tacoma).

With that, I have many many questions, and am not very electrically inclined. I have attached photos to show my battery area, as I don’t even know what half of these are and what I’d have to remove/swap out

- I do use shore power to do a minimal charge on the lithium through the existing converter, and use that shore power for winter camping, so don’t want to lose that.
- I know I’m supposed to have higher gauge wire from the truck to the camper, however does that mean I need to rewire the camper connection, based on it currently being an Atwood connector. If so, am I taking apart the insides?
- anything else I need to know? What about all these connectors (see photos).

Really just need an ELI5 on A) what I need, b) what I need to remove/stay and c) how to proceed with the wiring..

 

[Vic Harder]

The first picture is your battery separator. The DCDC will replace that component.
Not sure what the second picture is
3rd picture is a thermal fuse, likely 30A. I would replace this with a Blue Sea breaker sized appropriately for the DCDC you plan to use
4th picture appears to be focused on the buss bar.

Are you sure you need alternator charging given your usage patterns?

I would get the Victron 50A DCDC. PKYS is a decent reseller that I have used. No affiliation.
For safety, you will want a breaker as close as possible to the power source, in this case the truck battery
- The DCDC is not 100% efficient, and there are some power losses over the length of the run, so I would use a 60A breaker or larger, depending on the size of wire you choose to use
- I use Blue Sea 285 series breakers
- The breaker should be within a few inches of the truck battery. I mounted mine to the fuse box cover in the engine bay
- From there, run the wires under the cab of the truck until you get to the bed of the truck. Some folks choose to NOT drill holes, and simply go up and over the side of the bed. I have drilled holes and used simple plastic electrical grommets to run the wires through, and on the last build I used bulkhead passthroughs from Summit Racing. From there, I put on a set of Anderson Power Pole connectors (sized for the current and wire size) to a set of wires I would install by either following existing holes or drilling new ones through the wooden lower part of the camper, and terminate these two wires (+ve and -ve all the way from the truck battery) to the DCDC charger. There is no need for a breaker at the camper end, since the DCDC will only feed energy from the truck to the camper, not in the reverse direction.

I hope that helps. Oh, and wire size... I used Welding wire... designed for abuse! I sized my system for 100A, and used 2 AWG wire.

 

[ski3pin]

Vic, I believe the second photo is also the SurePower battery separator

 

[rubberlegs]

Cheapskate approach: Your power needs sound pretty small. Your battery may last quite a few days. Maybe you don't need to do anything, unless you plan to travel with little sun. What is your solar charger? Does it charge any in cloudy weather? Do you camp a lot in shade? Do you have a battery monitor that tells state of charge?

Our shore power charger takes a day and a half to charge our lithium battery, so we do that at home. We have a small 12V fridge which in summer is the main power user, and can last 4 days. In winter the heater uses a similar amount. Our 90W solar panel is really only putting out about 50W typically, in full sun, but keeps up. I unplug our camper from the truck on trips less than four days.

I'd be tempted to "camp" at home for a week to see how your system keeps up... You can sleep in the house, but keep electrical stuff on while "camping"!

 

[Bcubed]

The first picture is your battery separator. The DCDC will replace that component.
Not sure what the second picture is
3rd picture is a thermal fuse, likely 30A. I would replace this with a Blue Sea breaker sized appropriately for the DCDC you plan to use
4th picture appears to be focused on the buss bar.

Are you sure you need alternator charging given your usage patterns?

I would get the Victron 50A DCDC. PKYS is a decent reseller that I have used. No affiliation.
For safety, you will want a breaker as close as possible to the power source, in this case the truck battery
- The DCDC is not 100% efficient, and there are some power losses over the length of the run, so I would use a 60A breaker or larger, depending on the size of wire you choose to use
- I use Blue Sea 285 series breakers
- The breaker should be within a few inches of the truck battery. I mounted mine to the fuse box cover in the engine bay
- From there, run the wires under the cab of the truck until you get to the bed of the truck. Some folks choose to NOT drill holes, and simply go up and over the side of the bed. I have drilled holes and used simple plastic electrical grommets to run the wires through, and on the last build I used bulkhead passthroughs from Summit Racing. From there, I put on a set of Anderson Power Pole connectors (sized for the current and wire size) to a set of wires I would install by either following existing holes or drilling new ones through the wooden lower part of the camper, and terminate these two wires (+ve and -ve all the way from the truck battery) to the DCDC charger. There is no need for a breaker at the camper end, since the DCDC will only feed energy from the truck to the camper, not in the reverse direction.

I hope that helps. Oh, and wire size... I used Welding wire... designed for abuse! I sized my system for 100A, and used 2 AWG wire.

Exactly what I needed. Thank you. Do I need to mess with anything on the bus bar?

 

[Vic Harder]

well, if the separator connects to the buss bar, then those wires need to removed too. Or were you asking something else?
Oh, and the thermal fuse in the camper can be removed, as the 60+Amp breaker in the engine bay will replace that.

 

[Doods]

This was my spring/summer project this year. My Victron 12/12-18 works well but it will not put out the full power from my Tacoma alternator. It works great if I manually turn on and off the ignition detection so I know it is not a setup or wiring issue but the Toyota smart alternator. I am not as familiar with Tundras but I have seen them popup in discussions and trouble shooting. I am planning to run an ignition wire per the Victron manual later this week. Good luck. The upgrade for us has been wonderful even with this small hiccup.

 

[Jon R]

This was my spring/summer project this year. My Victron 12/12-18 works well but it will not put out the full power from my Tacoma alternator. It works great if I manually turn on and off the ignition detection so I know it is not a setup or wiring issue but the Toyota smart alternator. I am not as familiar with Tundras but I have seen them popup in discussions and trouble shooting. I am planning to run an ignition wire per the Victron manual later this week. Good luck. The upgrade for us has been wonderful even with this small hiccup.

Have you carefully read the section in the charger manual on setting up the engine running detection logic? If your charger can produce full current from the smart alternator when using a hardwired ignition on signal, it should be able to do the same if you can get the engine running detection logic settings adjusted so the charger does not need to keep cycling on and off to verify the engine is still running.