DC to DC converter necessary when switching to lithium batteries?

[edlynnrich]

Originally Posted by Vermilye

Make sure it is powered by the tow vehicle or other 12V source. The device remains off until it sees input voltage.

Thanks Jon. I didn’t realize that. I had thought the converter received power from the trailer battery and the TV. I have an 2021 F150 so I’ll have to sort out when the truck is powering up the charge circuit.

Ed

[Vermilye]

Originally Posted by edlynnrich

Thanks Jon. I didn’t realize that. I had thought the converter received power from the trailer battery and the TV. I have an 2021 F150 so I’ll have to sort out when the truck is powering up the charge circuit.

Ed

If it helps, with my 2018 F150 I have to step on the brake, put the shifter in gear, and after a couple of seconds the tow charge line comes on. Not sure that putting the truck in gear is necessary - some have said just stepping on the brake for 3 seconds does the same. In any case, it stays on even after shifting to park & doesn't go off until you shut off the engine. It does not have to be set in Tow/Haul.

[JimB]

For my 2021 F150 I actually have to be in drive and move the vehicle before the charger is supplied power and is seen by the app. Apparently Ford decided to do this to prevent accidental discharge of truck battery when plugged in and not running.

[AuthorSP]

Hi folks, I am reading through this because we have a 5.0 on order and plan to have the lithium and 2 solar panels option. If I understand correctly, we can have our tow vehicle charge the trailer's lithium batteries while we drive (in addition to the solar), but to do so, we need some sort of interface, which is Victron if supplied by ETI. Do I have all this right so far?

It really gets confusing reading through the comments, and makes me wonder if there are more drawbacks than advantage to this? Can anyone lay out the best approach in layman's terms for me? Thanks!

[bborzell]

Originally Posted by AuthorSP

Hi folks, I am reading through this because we have a 5.0 on order and plan to have the lithium and 2 solar panels option. If I understand correctly, we can have our tow vehicle charge the trailer's lithium batteries while we drive (in addition to the solar), but to do so, we need some sort of interface, which is Victron if supplied by ETI. Do I have all this right so far?

It really gets confusing reading through the comments, and makes me wonder if there are more drawbacks than advantage to this? Can anyone lay out the best approach in layman's terms for me? Thanks!

If you are specifying the full solar package, it includes the Victron DC-DC charger.

[the5reeds]

I installed a Victron 12/12-30 DC to DC converter in my 19 in conjunction with my Ridgeline truck. Because the 7-pin plug wiring is insufficient for 30a charging I installed a small breaker and 6 awg wire from the truck's battery to an Anderson SB50 connector on the rear. when I tow and need the truck to charge, I plug a short cable with Anderson connectors on each end to the truck and to the trailer to make the connection. It's worked well when I want to leave the fridge in DC mode. I also have a longer cable with Anderson connectors in case I just want to use to truck as a "generator" while boondocking.

[AuthorSP]

What are Anderson connectors? Is this something we can buy or have to make?
Thanks!

[the5reeds]

Originally Posted by AuthorSP

What are Anderson connectors? Is this something we can buy or have to make?
Thanks!

you can probably buy some short cables with Anderson connectors, but I just make mine using 6 awg jumper cables

this is what I used on the back of the truck

these are the connectors for the cables

you'll need a crimper like this one

circuit breaker

[alanerickson]

PowerWerx also has an ample assortment of Anderson connectors. Not sure how their prices compare. Probably not as cheap as amazon. They do a lot of custom cables though and I'm betting they could probably put together a corded plug for more money but less work on your part. Just another option.

https://powerwerx.com/anderson-power...-sb-connectors

I switched to the lower amp Renogy charger since I would have been pulling a little over 22A and my truck wiring is rated for 21A in continuous situations. Switching it was more work than expected, mostly due to the ring connectors; and if I had to do it again I'd look long and hard at running a separate power cable and going with an Anderson connector.

[richardr]

Instead of installing a DC to DC converter, I disconnected the tow vehicle charge wire in the junction box attached to the trailer frame. As far as I can tell the only affect is my lithium trailer batteries are now charged only from the solar panel when I'm driving.

[cpaharley2008]

Originally Posted by richardr

Instead of installing a DC to DC converter, I disconnected the tow vehicle charge wire in the junction box attached to the trailer frame. As far as I can tell the only affect is my lithium trailer batteries are now charged only from the solar panel when I'm driving.

Make sure your trailer brakes are still activated.....

[richardr]

Originally Posted by cpaharley2008

Make sure your trailer brakes are still activated.....

Yes, the brakes get power from the brake controller through the blue wire.

[BobG]

I also disconnected the tow vehicle charge wire and rely on the solar.

[edlynnrich]

Originally Posted by Vermilye

If it helps, with my 2018 F150 I have to step on the brake, put the shifter in gear, and after a couple of seconds the tow charge line comes on. Not sure that putting the truck in gear is necessary - some have said just stepping on the brake for 3 seconds does the same. In any case, it stays on even after shifting to park & doesn't go off until you shut off the engine. It does not have to be set in Tow/Haul.

Thanks Jon. I’ll mess with it when we get home. Although I’m not sure how useful making a Bluetooth connection will be if I can’t see what the Victron is doing while driving.

[edlynnrich]

Originally Posted by JimB

For my 2021 F150 I actually have to be in drive and move the vehicle before the charger is supplied power and is seen by the app. Apparently Ford decided to do this to prevent accidental discharge of truck battery when plugged in and not running.

This appears to be even more complicated than Jon’s 2018. Did you find any benefit in making a connection?