How to lower charge voltage

[Rbertalotto]

Anyway to lower voltage?.....My camper has a WFCO converter/charger. It is set up for Lithium but it outputs 14.6v. I spoke with my Li battery manufacturer and they said not to charge the two 12v/100ah batteries over 14.4v. Is there any way to limit the output of the charger to 14.2? I have 12v TVs in the camper that can not tolerate over 12.5v so I have "Buck" converters on each TV. But I'm not aware of a buck converter that can handle 45amps that the charger outputs.

 

[sunshine_eggo]

Doubt it.

14.6V is safe for LFP, but it requires near perfect balance on the cells. If you dropped the LFP where the lead-acid was, you likely have notable voltage drop between the WFCO and the batteries meaning the time spent at 14.6V will probably be pretty short.

This is yet another reason why these "lithium" converters are mostly a scam. Most are shitty implementations seemingly based on a complete ignorance of the subject.

Can you change the settings to something besides Lithium?

 

[time2roll]

Does the WFCO have a user selection to choose regular flooded lead acid? That used to be 14.4 volts.

Otherwise a standard Progressive dynamics goes 14.4 or a Powermax Boondocker has adjustable voltage.

https://powermaxconverters.com/product/pm3-mba/

Meanwell also makes some battery chargers that would work.

https://www.trcelectronics.com/View/Mean-Well/NPB-750-12.shtml

 

[Rbertalotto]

Thinking about this a bit more....I'd love to rewire this whole thing with all Victron...But space and money...and time...limit that option. I already have a good Inverter....What I need is a charger / CONVERTER....Charge the batteries and run the trailer on 120V when plugged in. I have a Victron BlueSmart 12/30 charger that can also be used as a CONVERTER. But to do so you need to go into the programming every time. With 30a max output, I don't think it could handle all the 12 loads I have and/or keep the batteries charged......But then again, I have 420w of solar on the roof too.....Maybe forget about the CONVERTER aspect and always run the trailer off the batteries/charger/solar.......Comments?

 

[Rbertalotto]

Does the WFCO have a user selection to choose regular flooded lead acid? That used to be 14.4 volts.

Yes it does......But that would be a three or four phase charge profile.........I actually removed the LED charger/converter module and replaced it with the Li version.....Maybe I should have just let it be?

 

[Rbertalotto]

POWER MAX....Darn! Why didn't you tell me about this unit before!!!

This looks like EXACTLY what I need and a direct replacement for the WFCO module. Strange I never stumbled upon it two years ago when I was doing this conversion. THANK YOU!

 

[time2roll]

My converter (wfco) has been disabled for years. 100% solar. Just remains there for if conditions get difficult.

 

[Rbertalotto]

I think that might be the best plan.....

 

[sunshine_eggo]

The WFCO will be good for generator charging because that's where the typical lead-acid converter falls short for LFP.

Recommend you revisit the 3 phase option and let us know what the voltages are. The vast majority of them will charge the battery to very near full on shore power, but it may take several hours at the typical 13.6-13.8 "absorption" voltage and typical wiring losses.

 

[Rbertalotto]

I started another UPDATE thread on this charging situation....

 

[12VoltInstalls]

What I need is a charger / CONVERTER....Charge the batteries and run the trailer on 120V when plugged in.

I may be an odd duck but I am nonplussed with RV coinverter arrangements from the oem. Because they don’t charge well imho and there’s a lot of heat that leaves them = inefficiency.

....Maybe forget about the CONVERTER aspect and always run the trailer off the batteries/charger/solar.......Comments

This is where an AIO shines.
With their automatic transfer switch built in and robust utility chargers they make sense in many cases. MPPSolar 1012LV-MK permits sufficient solar to charge and run it but at ~28W idle consumption can be less optimal. Eliminates the converter need altogether imho.
Alternatively, separate individual components can cut idle current to <=12W for some equipment.

With 30a max output, I don't think it could handle all the 12 loads I have and/or keep the batteries charged

always run the trailer off the batteries/charger/solar......

That’s what I do. I modified an older “4-season” 25’ camper to permit practical 12-month use aka stationary RV.

Since you’re 12V heavy what I’d suggest is more panels and more battery storage with a 12V system and keep the converter disabled unless ‘emergency’ comes up.