How to turn off built-in DC Convertor

[BillM321]

Hello all,

I have a 2021 XLS 22MLE and I am thinking about installing a LiFePo battery in the front storage compartment or possibly under the bed, once Spring camping season rolls around. I have seen where folks sometimes install a stand-alone Lithium specific charger in the front storage compartment and plug it into the GFCI outlet on convenience bay in the front storage. They always refer to turning off the breaker for the OEM DC convertor in the power center so that only the Lithium specific charger is actually supplying DC power.

I was assuming that there would be a breaker for just the DC convertor in my power center, but I do not see one. Am I missing something here? Is there possibly another breaker inside the power center somewhere that turns off the built in OEM DC convertor? Or does the small power center they use in a 22MLE just not have a dedicated breaker for the DC convertor/charger?

If I can't disable the built-in OEM convertor then I am going to have to rethink my whole plan for charging my LiFePo battery. I have read that many folks use the OEM charger on Lithium batteries, but that seems like a waste as I don't think I would ever fully charge my Lithium battery using a charger designed for Lead-Acid. And not to mention the loss from DC voltage drop across the long run of small gauge wires that are installed from the Power Center to the battery.

Any input would be greatly appreciated.

Thank you,
BillM321

[ncitro]

Hello all,

I have a 2021 XLS 22MLE and I am thinking about installing a LiFePo battery in the front storage compartment or possibly under the bed, once Spring camping season rolls around. I have seen where folks sometimes install a stand-alone Lithium specific charger in the front storage compartment and plug it into the GFCI outlet on convenience bay in the front storage. They always refer to turning off the breaker for the OEM DC convertor in the power center so that only the Lithium specific charger is actually supplying DC power.

I was assuming that there would be a breaker for just the DC convertor in my power center, but I do not see one. Am I missing something here? Is there possibly another breaker inside the power center somewhere that turns off the built in OEM DC convertor? Or does the small power center they use in a 22MLE just not have a dedicated breaker for the DC convertor/charger?

If I can't disable the built-in OEM convertor then I am going to have to rethink my whole plan for charging my LiFePo battery. I have read that many folks use the OEM charger on Lithium batteries, but that seems like a waste as I don't think I would ever fully charge my Lithium battery using a charger designed for Lead-Acid. And not to mention the loss from DC voltage drop across the long run of small gauge wires that are installed from the Power Center to the battery.

Any input would be greatly appreciated.

Thank you,
BillM321

I'm not familiar with that power center, but on ask the ones I've seen either you pull the cover off of the power center and it's there or you get to it from the back side (usually a false wall comes down in the pass through storage). Once you can access the actual converter you'll probably find it plugged into an outlet, and you can just unplug it. If it's hard wired you'll have to either cut the wires and cap them off, or better yet trace them back and disconnect them.

[howson]

Any input would be greatly appreciated.

According to the GD Parts Lookup website (link on menu bar above) the system in your trailer is a WFCO- 8735P. https://www.granddesignrv.com/owner-...s/detail/42835

The manual is here: https://wfcoelectronics.com/product/wf-8735-35-amp/

Lots of threads here on the forum if you search for "WFCO" or "8735". One in particular you'll find interesting as it mentions a replacement (WF-8735LiS): https://gdrvowners.com/forum/operati...er-center-swap

For your specific question about the breaker for the converter, it appears to me that WFCO is running the converter off of the main 120vAC/30A circuit breaker.

The output of the WFCO is protected by the 30A fuse in position 6 and the 40A reverse polarity fuse in position 7.

The following assumes you're familiar working around electricity and know how to keep yourself safe. If unsure, consult a qualified individual to help you!

The swap to the lithium-capable version of the power center seems like the easiest solution (see previously linked thread) but it you want to experiment to see if a separate charger (remember the device serves two purposes--charger and converter) is a possibility this is what I'd try:

1) Turn off the battery disconnect switch and disconnect from shore power. (You could also disconnect the battery...but that's really going overboard to be "safe".)

2) Remove the 30A fuse in slot 6.

3) Turn on the battery disconnect and test the 12v devices in your trailer. Lights work? Slide work? Water pump? Furnace?

• If nothing works replacing the entire WFCO.is the only viable option IMO.
• If everything still works...the converter is still powering your trailer's 12v circuits (good) so press on!

4) With a multimeter, check battery voltage (to get a starting point).

5) Plug in to shore power and check battery voltage again. Did it increase or stay the same?

• If the voltage increased the 30A fuse didn't stop the charger function from charging the battery. (It shouldn't...) Replacing the WFCO with the lithium version is the best option.
• If the battery stayed the same that means you've isolated the WFCO's charger output but the converter side still powers the trailer--that means you could add a dedicated charger elsewhere.

Let me repeat the best, and easiest, option appears to be to install the lithium-specific WF-8735LiS.

ncitro , TucsonJim or the other electrical-smart folks--please double-check my steps above and if I screwed something up chime in.

Howard

[TucsonJim]

Howard has done the homework and identified a lithium dedicated converter. If it were me, I'd replace the converter and be done with it. That's actually what I did in my rig.

Jim

[JBRV2020]

Amazon.com: WFCO WF-8950L2-MBA Replacement RV Power Converter Lithium-Ion Main Board: Automotive

Not sure if yours is the same. But when I called them they said to just buy this and it is a 3 to 10 minute install.

[howson]

Amazon.com: WFCO WF-8950L2-MBA Replacement RV Power Converter Lithium-Ion Main Board: Automotive

Not sure if yours is the same. But when I called them they said to just buy this and it is a 3 to 10 minute install.

We've discussed that replacement in the past but couldn't find a reference to it, and the manual for Bill's WFCO didn't show the location of the converter.

BillM321 -- suggest following up JBRV2020 's post by verifying (through WFCO) that it does indeed fit your Power Center. If you do the swap, pics of the process and a short write-up would be much appreciated.

Howard

[gbkims]

The 8700 Series and 8900 Series of Power Centers look to be different layout and size.

8700 https://wfcoelectronics.com/product-...f-8700-series/
8900 https://wfcoelectronics.com/product-...f-8900-series/

WFCO does sell 8700 Series Lithium Power Centers as well as 8900 Lithium Series.
The WF-8950L2-MBA replacement looks like it's for WF-8900 series.

[ncitro]

I would personally go with a deck mounted converter rather than replacing the one in the power center. That would allow you to locate it closer to the batteries for more efficient charging. Also you can run larger wires to the battery, and they would be shorter so less expensive.

[mbopp]

I'm running dual 6V batteries. For faster charging off a generator I installed a stand-alone converter inside the pass-through hookup center. I was fortunate that the WFCO was on its own breaker so it's turned off but still available as a backup.

[Yoda]

The swap to the lithium-capable version of the power center seems like the easiest solution

Howard

This thread is perfect timing. I am researching the same issue. My converter is enclosed/attached to the back of power distribution panel.In the parts look up for my 2018 220RK its a combination unit, but brand and model number is not present. I know I can find the information in the GD folder - just need to look.

Just want to make sure I understand that the converter/charger part can be change out/removed (leaving distribution panel) and a replacement unit installed and tied to the power distribution panel? BB recommended a combination Victron converter/charger/ inverter unit. However I may want to install a different inverter that works off my Go Power solar controler In that case I just need a BB compatible converter / charger. Correct?????

Still trying to learn (frying a lot of gray cells)

Thanks for any help.
Keith

[howson]

Just want to make sure I understand that the converter/charger part can be change out/removed (leaving distribution panel) and a replacement unit installed and tied to the power distribution panel? BB recommended a combination Victron converter/charger/ inverter unit. However I may want to install a different inverter that works off my Go Power solar controler In that case I just need a BB compatible converter / charger. Correct?????:

As the lawyers would say, "it depends". What model WFCO power center is in your unit, Keith?

[Yoda]

As the lawyers would say, "it depends". What model WFCO power center is in your unit, Keith?

I braved the cold and cramped space (slide in makes a bit narrow for my wide body), got the model number off the distribution panel door. Its WF-8955PCE. The Operator Manual in the GD documents says WF-8900 series for use with WFCO Ultra III Distribution Center. I can get to the back if I can fit my (dimensionally challenged body) into the pass through and bend a bit - a lot of heater runs in the way, but I can probably undo them to get better access. Definitely a warm spring day project.

Specifications off the panel too;
Panel input 120V 60Hz 30A
Converter input 105-130V 60Hz 12A 950W
Converter output 13.6V 55A

There is a note that rating includes charging and load (whatever that means )


On a side note my 160W Go Power solar panel is putting out 4.4 to 4.6 amps this morning. I cleaned the snow off yesterday as battery (flooded) was at 53% charge, 12.2 volts. Now at 93% at 13.3V. Once fully charged I will pull the negative cable (or should it be positive?) Dang CRS! for the winter. SUMO springs tomorrow as it is supposed to be over 40 and sunny

Thanks
Keith

[howson]

I braved the cold and cramped space (slide in makes a bit narrow for my wide body), got the model number off the distribution panel door. Its WF-8955PCE. The Operator Manual in the GD documents says WF-8900 series for use with WFCO Ultra III Distribution Center. I can get to the back if I can fit my (dimensionally challenged body) into the pass through and bend a bit - a lot of heater runs in the way, but I can probably undo them to get better access. Definitely a warm spring day project.

Specifications off the panel too;
Panel input 120V 60Hz 30A
Converter input 105-130V 60Hz 12A 950W
Converter output 13.6V 55A

There is a note that rating includes charging and load (whatever that means )


On a side note my 160W Go Power solar panel is putting out 4.4 to 4.6 amps this morning. I cleaned the snow off yesterday as battery (flooded) was at 53% charge, 12.2 volts. Now at 93% at 13.3V. Once fully charged I will pull the negative cable (or should it be positive?) Dang CRS! for the winter. SUMO springs tomorrow as it is supposed to be over 40 and sunny

Thanks
Keith

Negative, Keith.

As gbkims noted in post 7, you're in luck with the 8900 series as it appears just the converter can be swapped to support a lithium battery.

[Yoda]

Negative, Keith.

As gbkims noted in post 7, you're in luck with the 8900 series as it appears just the converter can be swapped to support a lithium battery.

Thanks - I missed that post - sorry

[prahawalker]

We've discussed that replacement in the past but couldn't find a reference to it, and the manual for Bill's WFCO didn't show the location of the converter.

BillM321 -- suggest following up JBRV2020 's post by verifying (through WFCO) that it does indeed fit your Power Center. If you do the swap, pics of the process and a short write-up would be much appreciated.

Howard

I know this post is old but for sake of completeness, let me share a picture of the inside of the WF-8735P.
I have tried replacing the converter/charger section on the 8735P and it is not modular. The DC section is vertical and built in so the total unit is smaller. They don't make a unit to go inside this power center. Either change the whole unit out or add a stand-alone charger as mentioned above.
Jeff