Rockwood Lithium WFCO Auto Detect Converter Charger

[bleedwater]

I replaced OEM lead acid batteries in my 2022 Rockwood Mini-Lite 2513S with one BBGC3 270 Amp-hour Lithium battery. Knowing the OEM WF-8955 lead acid charger was not what I wanted, I spent a modest amount of dollars and effort to replace its converter with a drop-in-footprint WF-8955-AD-MBA (AD stands for Auto Detect) converter that is supposed to sense Lithium batteries and provide 13.68V DC charging or 14.6V DC charging for one to four hours if its computer program thinks the Lithium Battery needs 14.6V (WFCO support says its 14.6V decision is based on seeing over 20 Amps drawn from the converter for a predetermined interval of time). I hooked up a 2000-watt generator and got the WF-8955-AD-MBA converter working as designed and charging at 14.6V.

Here is my question to others on the forum who may have tried out this WF-8955-AD-MBA converter. Does anyone experience 55 Amps of battery charge getting into the battery? I covered my solar panel, turned off 1000 Watt inverter, turned off all other DC loads (leaving only .7 Amp DC load always present when battery switch is connected, turned off all AC breakers except main and converter then metered everything with generator on (although a perfect 30 AC Amp campground power connection produces the same results – not a generator shortfall) and recorded a video of volts, amps, and Victron Battery Monitor. The most current the battery ever accepted was 30 Amps DC for an instant and then charged dutifully while decreasing the charge current in the mid 20 Amp range for well over an hour while the BBGC3 SOC increased from 81% to 92%. That is less efficient than I would have expected. I was thinking that with all AC and DC loads off except the converter charging the battery, I would start with near 50 Amps of charging that decreased over time.

One more question if you have done this. The converter runs current to the battery mostly using OEM 8 AWG cable. I did not replace any OEM wiring, so the charging does have to take place over 8 AWG wiring. While wondering if voltage drop might be reducing the charge current, I traced the 8 AWG charge path from converter to battery and found that it connects in a metal external junction box but first passes thru a (SHORT STOP 24VDC C22 ??Amps??) mini breaker with a reset button on it. I cannot figure out its current rating since the current rating is unreadable on the case. Question: What is the current rating of this OEM Rockwood mini breaker? Need to find out because it may not in fact allow 50 Amps to pass through even if I could figure out a way to present 50 Amps of charge current to it.

[TitanMike]

To determine if your #8awg wire is limiting your charging current, first run your battery down to around 50% SOC or so. Then, with Solar Charging disconnected as well as other loads off, measure output voltage of converter at it's output terminals. Then measure voltage at the battery terminals themselves.

The difference in voltage will be the loss in the #8 wire.

Higher voltage at converter will fool it into thinking the battery is charged and switch output to lower level (absorb, float) and also reduce current.

Solutions-

Change converter
Larger gauge wire
Leave alone and let Solar handle job of fully charging battery.

As for the circuit breaker, if it's not tripping it's not affecting current flow.

[nvs4602]

My WF-8950L2-MBA which is 50amp lithum charger. Was charging at 46.7 amps. This was after I had discharged the battery until the BMS shut off. Then recharged to 100% no current draw.

I did this so the amp meter would calibrate to the full capacity of the battery. I would agree with TitanMike you need to discharge your battery to 50% or more to get the new converter to detect lithium battery.

Also on my converter it will not bulk charge at 14.6v for more than 4 hours. It will switch to 13.6v float charge after that. This happened at 4 hours 10 minutes on mine and battery was not 100% charged. You have to flip the breaker off and on to reset the 4 hours of bulk to get to 100%.

270ah ÷ 55amps = 4.9 hours to fully charge

[bleedwater]

Thanks TitanMike and nvs4602. Good points in both cases.

My charger sensed Lithium months ago and has stayed with the Lithium charging program ever since. Once it chose Lithium, it turned the program LED from Green to Blue indicating the charge program is Lithium. That history persists in non-volatile WFCO internal computer memory. Thus I am now always in the Lithium charging program.

In the Lithium charging program the WF-8955-AD-MBA will present one of two voltages: Absorption Mode = 13.6V and you stay there forever until the converter finds itself outputting 20 Amps DC for 30 seconds which will cause the converter to increase its voltage to Bulk Mode = 14.6 V. Nnvs4602 states correctly that that mode is limited to 4 hours.

My particular issue is I get the converter to switch from 13.6V to 14.6V and it is connected to a battery that is discharged by 60Ahr, so current ought to fly into that battery at the converter's max current limit, but instead it charges anywhere from 29 initially amps to 26 amps after 14 minutes.

The WFCO tech support team says check for voltage drop and see if that is what is limiting my current.

[nvs4602]

Check all of the crimped ends on the wires as well. While installing mine I found several bad crimped ends, which can also effect charge.

[JimM2109S]

Originally Posted by bleedwater

My charger sensed Lithium months ago and has stayed with the Lithium charging program ever since. Once it chose Lithium, it turned the program LED from Green to Blue indicating the charge program is Lithium. That history persists in non-volatile WFCO internal computer memory. Thus I am now always in the Lithium charging program.

Where is this color changing LED actually located? There is no reference to this in the WFCO product manuals, and I could not identify it when viewing an on-line picture of the circuit board.

I'm curious as I have Li batteries and factory solar. I'd like to confirm the AD made the right determination as the batteries were fully charged when installed.

[bleedwater]

Good point JimM2109S on no written WFCO documentation of the LED colors.

If you have a WF-89xx-AD-MBA converter with the Auto Detect feature,
this YouTube video on the WFCO channel explains it

https://youtu.be/-pFuVnUsPz4

There is also a YouTube channel called Love You RV that has three videos on the Auto Detect converter and sums it up with final thoughts after some long term usage.

[JimM2109S]

Thanks for that video. Why WFCO would “hide” the indicators behind a cover, or not document this in the manual is beyond me.

Guess I need to discharge my batteries and see if it has correctly identified my batteries.

[njfishing]

Was considering switching over to Lithium and swapping mine out or the 8955 AD as well. How difficult would this be for handy but electrically challenged person like me?

[TitanMike]

Originally Posted by njfishing

Was considering switching over to Lithium and swapping mine out or the 8955 AD as well. How difficult would this be for handy but electrically challenged person like me?

Generally changing the converter section in a WFCO Power Center is straight forward. Disconnecting the three wires on the 120 Volt AC side (Black, White, Green) and replacing the same colored wires from the new converter section in the same places. Then doing the same with the DC Wires on the 12 volt side.

Converter section is held in place with two machine screws.

Only tools required are a straight blade screwdriver and a Phillips screwdriver.

Take a picture with cell phone first so you have a visual record of which wires go where for both sides (120v and 12 v).

As for the battery connections, Pictures first then just disconnect and swap batteries.

The entire operation is pretty much "mechanical" and not much electrical knowledge is required. Just unplug shore power first for safety.

[njfishing]

Originally Posted by TitanMike

Generally changing the converter section in a WFCO Power Center is straight forward. Disconnecting the three wires on the 120 Volt AC side (Black, White, Green) and replacing the same colored wires from the new converter section in the same places. Then doing the same with the DC Wires on the 12 volt side.



Converter section is held in place with two machine screws.



Only tools required are a straight blade screwdriver and a Phillips screwdriver.



Take a picture with cell phone first so you have a visual record of which wires go where for both sides (120v and 12 v).



As for the battery connections, Pictures first then just disconnect and swap batteries.



The entire operation is pretty much "mechanical" and not much electrical knowledge is required. Just unplug shore power first for safety.

Thanks for that Titan! My lead acid is going on 3 years now so when it goes I think I’ll switch over to lithium. We don’t dry camp much so thinking the 100 amp hour Chins and if we decide to dry camping more, I can always add another. Thoughts on that? CHINS LiFePO4 Battery 12V 100AH Lithium Battery - Built-in 100A BMS, Perfect for Replacing Most of Backup Power, Home Energy Storage and Off-Grid etc. https://a.co/d/c64fx6I

[TitanMike]

Originally Posted by njfishing

Thanks for that Titan! My lead acid is going on 3 years now so when it goes I think I’ll switch over to lithium. We don’t dry camp much so thinking the 100 amp hour Chins and if we decide to dry camping more, I can always add another. Thoughts on that? CHINS LiFePO4 Battery 12V 100AH Lithium Battery - Built-in 100A BMS, Perfect for Replacing Most of Backup Power, Home Energy Storage and Off-Grid etc. https://a.co/d/c64fx6I

I don't really have an opinion of the Chins batteries although many think highly of them. I have Battleborns that I've been using since 2019 with no issues at all.

Even though you don't dry camp much, when you do you will want to be able to run all the necessities for a reasonable amount of time before having to recharge (generator, power post, etc). Before making a decision on the battery size I would take inventory of your power needs for each 24 hour interval. Furnace, Lights, refrigerator (if a residential type), water pump, TV/DVD Player, etc.

Using my TT as an example I find that my 24 hour consumption for furnace during cool weather, a movie at night, my radio during the day (a couple hours avg) and the normal lights, water pump, refrgerator controls (mine is LPG/120v) runs 35-50 amp hours depending on outside temperature.

A 100 ah battery would be adequate for a 24-36 hours safely. If wanting to run an entire weekend I would consider either a pair of 100 ah LiFePo4 batteries or a single 200 ah battery. which would be more than enough for a long weekend "off the grid".

Just my thoughts.

[njfishing]

Originally Posted by TitanMike

I don't really have an opinion of the Chins batteries although many think highly of them. I have Battleborns that I've been using since 2019 with no issues at all.

Even though you don't dry camp much, when you do you will want to be able to run all the necessities for a reasonable amount of time before having to recharge (generator, power post, etc). Before making a decision on the battery size I would take inventory of your power needs for each 24 hour interval. Furnace, Lights, refrigerator (if a residential type), water pump, TV/DVD Player, etc.

Using my TT as an example I find that my 24 hour consumption for furnace during cool weather, a movie at night, my radio during the day (a couple hours avg) and the normal lights, water pump, refrgerator controls (mine is LPG/120v) runs 35-50 amp hours depending on outside temperature.

A 100 ah battery would be adequate for a 24-36 hours safely. If wanting to run an entire weekend I would consider either a pair of 100 ah LiFePo4 batteries or a single 200 ah battery. which would be more than enough for a long weekend "off the grid".

Just my thoughts.

Thanks again Titan... Gas/electric fridge and no inverter so no TV etc but if it was going to be cold, I would want run the furnace so would plan to bring my 3200 Firman generator. Had a Roo Hybrid with two 6 volt golf carts and one fall trip we took it got down into the 40s at night. Ran the genny for a few hours in the AM and the PM each day but one night it got real cold and the furnace quit at 4 AM. I like that the Lithium batteries with the correct charger take a lot less time to re charge and they have more usable amp hours so thinking this would solve that problem.

[TitanMike]

Originally Posted by njfishing

I like that the Lithium batteries with the correct charger take a lot less time to re charge and they have more usable amp hours so thinking this would solve that problem.

I can charge my two Battleborn batteries from 60% depth of discharge to 100% in ~2.5 hours of generator run time. That was with my Progressive Dynamics 60 amp "Lithium" charger (single 14.6 volt stage) unit. It put out a continuous 57 amp charge current.

I recently (like last week) upgraded it to a Phoenix IP43 Smart Charger that only puts out 50 amps but more than makes up for the lost 7 amps (It charged my batteries at 49.5 amps on it's first run) by providing three stages (Bulk/Absorb, Float, and Storage) for better battery care. Even at the lower output it charged my batteries from 25% DOD in one hour flat to 100%.

With a LiFePo4 battery bank you'll find that your generator run time can be cut nearly in half (or more) which is significant considering today's prices of gasoline.

[RedRoverComeOver]

Originally Posted by njfishing

Was considering switching over to Lithium and swapping mine out or the 8955 AD as well. How difficult would this be for handy but electrically challenged person like me?

Don't know the differences in wiring between your model and the one I replaced (WF-8735-AD), but sure the level of effort would be similar, especially if you're not an electrician. Just be leery when people say something is easy and can be done in no time. If you watch online videos, a lot of that stuff is edited and the not so fun stuff is typically not shown. You'll need more than a couple different screw drivers and new parts to do it all.

Took me 8 days from start to finish to replace the power center and worked the first time. Took another 2 days to replace two batteries, associated wiring etc. and worked the first time. Then there was load, discharge and charge testing that followed before actually taking it out on the first trip to test some more. My life doesn't revolve around an RV so I do things when I can and when I'm in the mood to screw with things I don't enjoy. It's not hard.

It's good advice of taking pictures but I'd go a step further and label all the wires to make things easier and for future reference. Random pics from the process.

[TitanMike]

Originally Posted by RedRoverComeOver

Don't know the differences in wiring between your model and the one I replaced (WF-8735-AD), but sure the level of effort would be similar, especially if you're not an electrician. Just be leery when people say something is easy and can be done in no time. If you watch online videos, a lot of that stuff is edited and the not so fun stuff is typically not shown. You'll need more than a couple different screw drivers and new parts to do it all.

Took me 8 days from start to finish to replace the power center and worked the first time. Took another 2 days to replace two batteries, associated wiring etc. and worked the first time. Then there was load, discharge and charge testing that followed before actually taking it out on the first trip to test some more. My life doesn't revolve around an RV so I do things when I can and when I'm in the mood to screw with things I don't enjoy. It's not hard.

It's good advice of taking pictures but I'd go a step further and label all the wires to make things easier and for future reference. Random pics from the process.

There is a big difference between replacing the full power center like you did versus just replacing the converter section in the WFCO 8955 power center.

On the OP's there's no need to remove all the wires you had to as yours and his are totally different.

You are totally correct that one should take lots of pictures, even draw diagrams, and tag wires, when working on one like yours.

As stated earlier, the OP's converter only has 3 120v wires and two 12 v wires that need to be disconnected/reconnected.

[njfishing]

Originally Posted by TitanMike

There is a big difference between replacing the full power center like you did versus just replacing the converter section in the WFCO 8955 power center.



On the OP's there's no need to remove all the wires you had to as yours and his are totally different.



You are totally correct that one should take lots of pictures, even draw diagrams, and tag wires, when working on one like yours.



As stated earlier, the OP's converter only has 3 120v wires and two 12 v wires that need to be disconnected/reconnected.

Hmm so rather than replace the whole power center you can just replace the converter section with a Lithium compatible one? That seems way easier since you’re only talking 5 wires…

[TitanMike]

Originally Posted by njfishing

Hmm so rather than replace the whole power center you can just replace the converter section with a Lithium compatible one? That seems way easier since you’re only talking 5 wires…

As long as that is an option. The smaller WFCO 8935 converter I believe requires more work.

My post was primarily to address the comment about not taking other's word about a converter change being simple and only taking a short time. For the OP's it is somple and definitely the way to go.

[jcarenz]

Originally Posted by TitanMike

I don't really have an opinion of the Chins batteries although many think highly of them. I have Battleborns that I've been using since 2019 with no issues at all.

Even though you don't dry camp much, when you do you will want to be able to run all the necessities for a reasonable amount of time before having to recharge (generator, power post, etc). Before making a decision on the battery size I would take inventory of your power needs for each 24 hour interval. Furnace, Lights, refrigerator (if a residential type), water pump, TV/DVD Player, etc.

Using my TT as an example I find that my 24 hour consumption for furnace during cool weather, a movie at night, my radio during the day (a couple hours avg) and the normal lights, water pump, refrgerator controls (mine is LPG/120v) runs 35-50 amp hours depending on outside temperature.

A 100 ah battery would be adequate for a 24-36 hours safely. If wanting to run an entire weekend I would consider either a pair of 100 ah LiFePo4 batteries or a single 200 ah battery. which would be more than enough for a long weekend "off the grid".

Just my thoughts.

Just an FYI. There are vendors on Amazon (Power Queen and Ampere Time) that are offering a 190AH 12v LifeP04 battery for just a little over $600. they look to be the same battery, just different case colors.

I personally just bought the Power Queen 190AH Direct from their website (ipowerqueen.com). these are Chinese made batteries, but to be honest, even the high end US companies selling Lithium are sourcing the cells from China, likely from the same vendors the Chines companies are using. And bot of the afore mentioned vendors have warehouses in CA, so your ship time is 3-5 days.

The reason i went with the Power queen was this review by hobotech:

https://www.youtube.com/watch?v=_EkeH42_tB8

.

BTW: I upgraded my converter to the WFCO WF-8955lis, which is switchable from LA to Lithium. I've tested and it does hit the higher voltage when initially connected. If the battery is already near full SOC it stays at about 14.4v-14.6v for a minimum of 1 hour, then drops to absorption @13.6v. I've yet to deplete the battery below 60% SOC to see if the claim of 4 hours Max at 14.6v happens. i intend to find out this weekend, when i will be dry camping from Friday to Sunday.

As to the amps at the battery, you will likely never get close to the full 55 Amps at the battery unless your battery is right next to the converter.

Also, keep in mind, the amps you can draw through the converter are going to be limited by; 1 - The generators max clean amp output; 2 - The draw from any other 12v drain from your RV (think stereo \ clock \ water pump, etc.) and; 3 - Limitation on what your RVs shore power can handle - you will not get more than 30 Amps from a 30 amp input.

[JCR]

Do these Lithium Batteries charge while driving ..(vehicle alternator ) or will damage result ?? Do these batteries require special charging requirements ?