WFCO Charger/Power Supply

Josh,

WFCO is famous for not going into bulk.

Have you looked at SiO2 batteries?

As Piano said the WFCO is famous for that.
Some folks have said it's a simple fix (Don't have one so can't advise)
but I'd recommend Progressive Dynamics as the replacement.

IF the WFCO is a fuse/breaker/Converter assembly 4600 series

If it's a "Stand alone" (Not attached to the power distribution panel) 9200 series

In Both cases try to match the last two digits to the DC output of the WFCO.

jodeb720 wrote:

1. Is the output charging power fixed at 13.6 or does it move to 14.4 for bulk charging and taper down?

No

jodeb720 wrote:

3. Is this only good for charging FLA's or FLA's & AGM's?

Yes

If your friend thinks they might EVER find an inverter useful, NOW is the time to buy an inverter/charger/automatic transfer switch !
Remove the WFCO, install the inverter. Nothing to set (except battery type). Everything is automatic.

"Li is out of the price range as of today."

You apparently haven't looked at wet battery prices these days!

jodeb720 wrote:
My friend has a WFCO WF-8930/50 Power distribution

Questions:
1. Is the output charging power fixed at 13.6 or does it move to 14.4 for bulk charging and taper down?
2. Will the parasitic loads from the 5er "fool" the charging circuit into thinking it needs to continue at bulk or will it think it's in absorption phase of charging when it should be tapering for a finishing charge?
3. Is this only good for charging FLA's or FLA's & AGM's? Li is out of the price range as of today.
4. What is the output for this (I know it'll take either 50amp input or 30 amp input to the 5er - but they are usually rated for output - like 30 amps or 60 amps at 13.6)

Personally, I would advocate purchasing a stand alone good quality 3 stage charger and using that to recharge his battery bank(s) and just leave the WFCO in place.

Thanks in advance for the wisdom!

josh

1. It will do 14.4 automatically if it "sees" the trigger voltage under 13.2 on starting the charge. The key is the combined wiring and battery resistance between charger and battery. R goes up with higher SOC, so the battery has to be low (just under 50% for a wet cell batt).

If the battery is at 12.3 before recharge as soon as you turn on the WFCO it will see maybe 13.3 too high to trigger it. If the battery is at 12.1 then the initial spike could be 13.1 and that will trigger the WFCO to boost.

Many RVs with WFCO have higher R wiring (long and too thin) which adds R and makes the initial spike go aboe 13.2 so the WFCO does not trigger even though the battery is low enough.

2. No, parasitic not enough to make the WFCO see its trigger

3. AGMs have a higher resting voltage than wets so a "low" AGM has a higher voltage and that makes it harder for the WFCO to see under 13.2 on starting.

Li LFP have low R so that would help with the trigger but they have even higher resting voltages per SOC than AGMs and Wets, so that makes it difficult to get under 13.2 but there might be a scenario with a very low SOC and low
R wiring, but doesn't seem likely IMO--but I have no measurements as examples for that.

4. Input is at nominal 120v whether you have a 50 or 30a shore power connection. Output is at nominal 12v DC so don't confuse the output rating with 120v input voltage.

30a indicates a smaller RV so any 30a or higher converter will do. However it is charging the battery, not running the RV you are asking about. In that case, you want a charger or converter that can do about 1/3 the amps of the battery bank's AH capacity, and be within the amps size the portable generator can run. need specifics on his gen size in watts (the "running watts" value not the "name" value--eg a "2000w" name does 1600 running) and the AH size of his battery bank to suggest a charger size in amps.

If I hit my low batteries during initial charging with the microwave/inverter the WFCO would boost every time. Yes the hurdle is to get voltage at the WFCO terminals well below 13.2 volts. Virtually impossible under normal use.

The WFCO will therefore chronically undercharge any deep cycle flooded or AGM battery. While camping the recharge will be very slow and tapering off above 65% charged. Need to run the generator 4 to 8+ hours.

Unless solar will be doing the charging, I recommend replacing the WFCO if camping off-grid.

time2roll wrote:
If I hit my low batteries during initial charging with the microwave/inverter the WFCO would boost every time. Yes the hurdle is to get voltage at the WFCO terminals well below 13.2 volts. Virtually impossible under normal use.

The WFCO will therefore chronically undercharge any deep cycle flooded or AGM battery. While camping the recharge will be very slow and tapering off above 65% charged. Need to run the generator 4 to 8+ hours.

Unless solar will be doing the charging, I recommend replacing the WFCO if camping off-grid.

My experience as well. Didn't believe the bad press about them totally until I got one with the new camper last year.
If we camped more or knew I was going to keep it a long time, that WFCO would have been in the garbage dump already.

short story, WFCO is a POS.

Thank you all so much for the advice!
As I suspected, and learned from so many of you over the years here, WFCO's are not the "bell of the ball".

Personally, I left my WFCO in my 5er and charge my battery banks by a separate vectron battery charger someone recommended all those years ago... It works well and does the job.

My friend will probably go the inverter/charger route with a built in transfer switch from PD. That's what I'm going to take back to him.

lwiddis - I am going to take a trip to costco (hopefully) tomorrow to look over the GC's they have in inventory. I'm sure I'll be in for a sticker shock but every time I got to market, I'm in sticker shock there. It's like 1979 all over again (Inflation!)

Again, thanks so much!!

to add to the WFCO operation.
WFCO stuffs high current into the battery at startup and looks at the voltage AT the charger. if it is above about 13.2V it goes to bulk mode. Therein lies the major issues (a) the voltage at the battery terminals PLUS the voltage drop along the line must be low enough to go below the threshold.
(b) stuffing current in then looking at voltage is the opposite of what PD and others do, which is to look at battery voltage make a decision, then act and track.

There are tricks with the WFCO, like running a microwave on an inverter, especially with GC2 batteries to get the voltage enough under the threshold to get the WFCO into bulk mode and have it stay there.

easier is to toss the WFCO and go with a PD or other good drop in.

Can't count the times we've been boondocking and people ask how we can only run the genny an hour or so, while they need hours and still have not much battery. I grab my clamp on amp meter and show then the WFCO is only giving them 10-15A charging current and 13.6V not the 50A claimed.