DC/DC Charger Prep
- Thread starter George
- Start date
BryanValRox
Well-known member
Geo, this has been discussed here before and I don’t recall Alliance ever chimeing in to say this is why we did this.
We ordered our 2024 310RL with the disc brake option, I was under the impression that this option drove the DC/DC to the Bill of Materials. The why remains a bit of a mystery at this point.
I had previously post the theory of a more control charge rate to the battery, given there is standard Solar installed, so solar and the truck would be adding to the battery. The charging unit also acts as a battery isolator, so they may have added it to prevent the solar from affecting the truck while hooked up and off.
Whatever the reason for the install, our truck charge line feeds the input side of the DC/DC , the trigger line to activate it was originally hooked to the 7 pin marker light circuit. I changed it on my to trigger from the charge line, just in case I forgot to turn the lights on manually do to the auto light feature on my truck being my normal default.
I would bet it will take a phone call to Alliance Service and their electrical engineer to get to the bottom of the why for use.
As far as checking to see if your truck is charging the battery, that would be easily determined with a multimeter.
Disable your solar master, hooked up your meter leads to the battery and plug your truck in and take your measurements.
BryanValRox
Well-known member
George, search by Disc Brake or Brakes once , it should take you to several posts involving DC/DC. I tried to post the link here and ended up deleted it , I did something wrong and it didn’t copy the whole post.
Jim Beletti
Well-known member
rbflapjack
Active member
George, did you ever use a multimeter to check if your TV is charging your battery? I have the same question.
George
Well-known member
I did not use a multimeter but I did look at my Renogy battery shunt and it appears to be charging while the truck is running.
rbflapjack
Active member
Thanks. I'll check mine through the battery BMS. I still don't understand what the leads labeled DC/DC prep are for though.
BryanValRox
Well-known member
These leads would be hooked to a DC/DC charger if your unit contains one. The charger would manage the Tow vehicle charge rate to the coach battery more accurately. It also acts as an isolator when not triggered in the on position to prevent the coach from draining the TV battery . It also can be set for different charge rates for a given battery type. For example, your TV might have a FLA type and your coach might have a Lithium type.
You can easily check your coach battery for charging with a multimeter hooked to the coach battery . Turn your solar off, hook up your meter to the coach battery and hook your 7 pin to the truck and start it up. The voltage on the meter should jump up close to the trucks charge output.
Generally speaking TV’s charge coach battery or batteries as standard practice. Yes there are exceptions, and I believe the Valor Model is one of them. I ran across a document about this sometime back, can’t remember if it was all Valor or just Super Solar equipped models.
2 Allies
Well-known member
The DC to DC prep is for the addition of a DC to DC charger if so desired. Your 7-pin connector only supply's a very minimal charge not enough to keep up with a 12 voltage fridge. So on overcast days or at night while traveling, you would need to add a dc to dc charger to charge your battery (s) while towing especially if you plan to boondock. Your battery would fully charge on long tow days.
You can check out a YouTube video on the subject to get more understanding.
Hope this helps,
You can check out a YouTube video on the subject to get more understanding.
Hope this helps,
Just for clarification - if you are planning to use a DC-DC charger you will need to pull a heavy cable from the front of the truck to the DC-DC charger. You will not really get any gains from using the 7-pin for that. I imagine we all know that, but I just wanted to make sure it was said.
I can't tell the gauge of the wire in the image, but I used 4 AWG for my 50 amp Victron Orion DC-to-DC charger. I am guessing wire in the image might support up to a 15-20 amp DC-to-DC charger.
Using the new 120v outlet on some trucks might be a nice solution for sure. You should consider sending the power cord through the kingpin area and have it pop out in the front storage. (I did that for my dc-to-dc incoming power line) If you have Lithium batteries, a Victron smart charger would be next on my list. While you could clamp to battery(s) I would think they might vibrate off during travel. I would cut off the clamps and wire the incoming power directly to my 12v busbar. This allows the power to go to frig and charge battery with remaining power.
My truck does have a 400 watt out let in the bed, the Victron smart charger looks like perfect option. I'm planning on a 460 Ah Epoch battery for my camper but don't know which charger would work best. I see that the chargers are 120V but can't find the wattage they draw can you advise me on the best one. Thank you for the help.
Perhaps you can email Victron and ask them. I don't know the answer and I won't just simply guess.
BryanValRox
Well-known member
It certainly would be best to contact the manufacturer to get the specifics.
OHMS LAW would/should apply here, so you can do the math to figure it out and compare it to what the manufacturer shares with you.
Electrified
Member
Our 2024 F350 has the 2000 watt "generator" and I intend to run a extension cord of sorts through the pin box into the battery compartment where we will simply plug in the smart charger we purchased directly from Epoch when we bought our batteries. I hope this works as I really don't want to have to tie in a DC-DC charger from the battery all the way back.
That will work. But the 2024 F350 that is in your profile has a chase that makes it easier to run the wires for a DC to DC setup. I'm not typing with any practical experience just what I've been seeing on the web as I have the same MY truck and have been researching how to run the wires after @Oregon_Camper shared the challenges he had. I think the qualifier for this to be true is having the upfitter switches on your overhead console. What will you do with the red or black 12V wire from the 7pin once you go this route?