Travel trailer AC charger help

[Icestation]

Sorry newbie question, I have read so much stuff I start second guessing my needs/plan.

The stock charger I know is pretty weak but will it work for lifepo4 to just top off the pack when at a place with full hookups? Or do you recommend in just letting the solar (victron CC) maintain the batteries?
I have seen people saying no need to push 14.6v to lifepo4 when 13.8 gets to 99% soc. And all I seem to find is 14.6v chargers when searching for a AC charger for my trailer.

Also when the pickup is hooked up/towing it is sending 14.3 to the trailer I think only 10 amps, the 7pin has a charge wire with a fuse in the truck panel. I thought about just pulling that fuse out so while driving I will just have the solar on.

 

[ghostwriter66]

Sorry newbie question, I have read so much stuff I start second guessing my needs/plan.

The stock charger I know is pretty weak but will it work for lifepo4 to just top off the pack when at a place with full hookups? Or do you recommend in just letting the solar (victron CC) maintain the batteries?
I have seen people saying no need to push 14.6v to lifepo4 when 13.8 gets to 99% soc. And all I seem to find is 14.6v chargers when searching for a AC charger for my trailer.

Also when the pickup is hooked up/towing it is sending 14.3 to the trailer I think only 10 amps, the 7pin has a charge wire with a fuse in the truck panel. I thought about just pulling that fuse out so while driving I will just have the solar on.

First i guarantee that your stock truck is NOT pushing 10A while towing .. you might want to actually check that ... I am going to say less than 2A on a good day .. I know on some of the Chevy's at work before they are modified they are not even barely trickle charging the battery ...

What you could do is use your CURRENT RV charger to get the battery up to 13.8 and then have your SCC do the rest ... WHAT you do need to do is check what kind of charger it is and make sure that it does NOT have an equalization charge or that its doing something its not suppose to ... BUT technically you can run both your RV charger to get the batteries charged quicker -- and then it will kick off at 13.6 and you can have your SCC take over after that - without you having to do anything ...

Once again not sure how you have your RV set up but for the ones we work on - i think my way will work fine ...

NO NEED TO PULL THE FUZE .. if you do don't you loose lights and things also ??

 

[cass3825]

NO NEED TO PULL THE FUZE .. if you do don't you loose lights and things also ??

7-pin plugs have a dedicated charge wire, so pulling the fuse won’t affect brake or running lights.

 

[ghostwriter66]

7-pin plugs have a dedicated charge wire, so pulling the fuse won’t affect brake or running lights.

RGR .. still no need to pull it since it probably at best could pass 1A to the battery ...

 

[Icestation]

I will go test the current from the 7 pin, in a little bit.

As far as the AC charger, I will get the model number of the unit and look up if it actually has any charge cycles, my guess is it's pretty low end (dumb) charger.

 

[Icestation]

So I confirmed with a shunt and just got 8+ amps from my 7 pin connector on my stock 2018 Ford superduty. It has the trailer package and camper package so it has a relay and fuse for the #4 pin on the 7 pin connector when the electronics verify the trailer attached it will start charging. (My understanding is when you put it in gear, press the brake, that triggers the pickup to sense a battery or something and kick the relay to start charging)

I need to look up the specs on this charger.

Edit:

WFCO Technologies - Innovating the Future of RV Power

WFCO Technologies is committed to simplifying, enhancing, and optimizing every RV owner’s experience through advanced power technology and proven support.

wfcoelectronics.com

Converter Type	Three-Stage Converter Charger
Output Current	55 A
Voltage Output	13.2 – 14.4V DC Range
Absorption Mode (Nominal Voltage)	13.6V DC (nominal voltage)
Bulk Mode (Quick Charging Voltage)	14.4V DC (quick charging voltage)
Float Mode (Trickle Charge Voltage)	13.2V DC (trickle charge voltage)

Edit2:
So I could spend $220 on this ( https://wfcoelectronics.com/product/wf-8950l2-mba/ ) replacment, But it goes back to that is it necessary to charge lifepo4 at 14.6v, and at $220 is it worth it over what is currently in there? or are there other option?

Edit3: Lol, see way to much dang information rolling around in the brain.
Manufacturer says about my currect 8900 series

I guess I just need the stamp of approval from you experts.

 

[cass3825]

So I confirmed with a shunt and just got 8+ amps from my 7 pin connector on my stock 2018 Ford superduty. It has the trailer package and camper package so it has a relay and fuse for the #4 pin on the 7 pin connector when the electronics verify the trailer attached it will start charging. (My understanding is when you put it in gear, press the brake, that triggers the pickup to sense a battery or something and kick the relay to start charging)

	)

Most newer vehicles energize pin 4 when the ignition is on. This prevents the RV from draining the vehicle battery when parked without the vehicle running.

 

[Sgt Raven]

Most newer vehicles energize pin 4 when the ignition is on. This prevents the RV from draining the vehicle battery when parked without the vehicle running.

I've been telling others in a RV FaceBook group I'm a member of to check their 7 way with the ignition off and see if the pin is hot. There is still a bunch of late model vehicles without the relay for pin 4. One of the other members recently left his trailer plugged in while were at Disney and came out to a dead tow vehicle battery.

 

[Spleeft]

Im a noob but here's what Ive discovered with my TT.
I upgraded my stock WFCO to a PD 4655 Wildkat on the advice of the salesman to charge 2 - 6v seriesed Fullriver DC 220ah AGMs that are spekt for 14.7v for bulk and absorption and 13.6 float. The Victron BMV never went above 3.6v and it took 7 hours to replenish batteries that where down to 65% to 95% with the 4k Onan gen . The charger was doing 14.4 at the AC/DC panel but the batteries never saw above 13.6 because of inferior wiring is my guess ( 8 awg with at least a 35' round trip / crappy OEM factory wiring and connections / etc. ) . Now that my solar is hooked up on separate wiring, they are getting the full 14.7 and seem to charge perfectly. My point is maybe pay attention to wire run and proper gauging, ( or go one gauge thicker ), along with the other advise from the awsum pros here !

 

[Icestation]

I have a similar issue now, with my current 6v batteries, I just let the solar take care of them, since they are so low AH, it doesn't take much sun to charge them.
With the lifepo4 I figured I should "complete" the system and look at a better ac charger. But as I dive into this. It's looking less like I will gain anything, as the one I have now is only 3 stage. Is lithium approved (per manufacture).
You bring up a good point about poor wiring. I will do some testing on shore power this weekend to confirm actually charge voltage at the batteries.

 

[Electric Personality]

I bought the
WF-8950L2-MBA
Save your money. It never went into boost mode to 14.6, it is functionally exact to the original converter I replaced. Not sure how to get it to go to that voltage, using a 280 ah 4 cell eve DIY battery. The battery was discharged to 13.1 volts. Stopped charging at 13.64 volts.

 

[Electric Personality]

I bought the
WF-8950L2-MBA
Save your money. It never went into boost mode to 14.6, it is functionally exact to the original converter I replaced. Not sure how to get it to go to that voltage, using a 280 ah 4 cell eve DIY battery. The battery was discharged to 13.1 volts. Stopped charging at 13.64 volts.

Actually, I take that back.....
Just have to reboot it, and it jumps up for four hours to 14.6. Given the loss on the cable between battery and converter, it’s about dang near perfect.

 

[Chado]

So the 8950L2 is recommended? Recommended over the Progressive Dynamics PD4655LIV that is a replacement for the 8955? Pros cons of each?

 

[Electric Personality]

So the 8950L2 is recommended? Recommended over the Progressive Dynamics PD4655LIV that is a replacement for the 8955? Pros cons of each?

Well, I like it. It does fully charge my 280ah battery I built, and if it doesn’t, I just recycle the breaker. Since keeping the battery sizzling at 14.6, I think it is the better option than the PD power supply which just holds it at 14.6. I consider the PD an inferior product because of this, I want the system ‘wife’ proof.