Upgrading converter

Here's a clip from the WFCO site on their 8900 series (including the 8955) converters:

Automatic three-stage charging extends the life of your battery with output voltage modes of 13.2 VDC range “float” mode, 13.6 VDC range “absorption” mode, and a 14.4 VDC range “bulk” charge mode.The WF-8955 model provides 55 Amps and a clean, constant 13.6 VDC nominal output, for reliable operation of electronics and appliances. Automatic three-stage charging extends the life of your battery with output voltage modes of 13.2 VDC range “float” mode, 13.6 VDC range “absorption” mode, and a 14.4 VDC range “bulk” charge mode. Automatic three-stage charging extends the life of your battery with output voltage modes of 13.2 VDC range “float” mode, 13.6 VDC range “absorption” mode, and a 14.4 VDC range “bulk” charge mode.

The WFCO 8955 converter is NOT a single stage converter. While many claim it never goes into boost mode, my experience with that is that batteries are often mounted far from the converter and the voltage drop across the wire from battery to converter causes a false sense that the battery is fully charged. Nothing wrong with the converter that either relocation of batteries closer, or upgrading the battery to converter wire (to min #4 awg from standard #8 awg) won't solve.

That said, my old WFCO 8955 converter section now sits on a shelf in my shop and a Progressive Dynamic's deck mount converter is located within about a foot of my batteries (both LiFePo4).

I too suggest the Progressive Dynamics 4600 series. for a pair of GC-2 60 amp model is my suggestion. Progressive Dynamics factory is right here in the good old USA (Marshall Michigan a bit shout of the Brooks Memorial Fountain and Roundabout on old US-27 whatever they call it in the city and Industrial.. address is on Industrial. building faces Old 27. but entrance is on the side)

My original PD unit lasted 12.5 years of constant use the replacement outlasted the RV.

bestconverter finally got back to me and confirmed that there is no auto desulfation or manual control with the BD 1255 MBA 55 Amp 4-Stage Main Board Replacement. The price is great on these, but I want a smart charger and something with more control.

Instead they recommended the wildkat powered by progressive dynamics.

Looks like you mount the remote pendant somewhere more accessible which gives you more control. It claims to be a true, smart 4 stage charger, which would beat the **** out of my single stage. Anyone have any experience with these???

Thanks for all the replies!

lwiddis wrote:
Wet cell batteries determine the amount of charge they will accept tapering lower and lower as the SOC goes up. It is not based on time. For “fast” charging you can’t beat Lithium. Have you compared the cost long tern between the two? Have you considered solar for charging? Much easier than running a generator. I’m charging right now…no noise, no gasoline, no maintenance.

Moving to multistage saves me about 20 hours! Significant time saver. I would love lithium batteries but don't like the cost. Solar would be amazing as well, but we camp in the mountains a lot and I already have a genny. A multistage converter ticks all my boxes.

bgum wrote:
Let's see you have a 55 amp converter and want to change to a 55 amp converter to charge faster?

The WFCO 8955 PEC I have is a single stage. There is a HUGE difference in 55amp single stage charge at 13.6 vs 55amp 14.4 boost mode! Saves me about 20 hours in getting from 50% to 90%. Google multistage battery charging!

BFL13 wrote:
I am a big fan of those PowerMax LK converters (bestconverter rebrands his as in the OP) for their flexibility in choosing either automatic three stage or else choosing single stage adjustable so you can meet any battery spec but do it manually at the times required for your own scenario.

The problem with the OP lower portion type is after you install it, howinheck can you get at the setting controls???? The deck mount kind is easy. Just tuck it in under there with the side that has the two setting holes to the front so you can get at them.

On "four stage" vs "three stage" that is from some converters calling their fourth stage which comes on every so often (varies by brand how often) "equalization" when it is not. "Equalization" is an overcharge after the battery is full using say 16v to do a proper desulfation.

The "fourth stage" boost every so often to the 14.x "boost" voltage while it is in "storage" of 13.2v (third stage), is actually just to stir the electrolyte and should be called "de-stratification"

Anyway, you can get a deck mount 60 amper in there and find a way to get 120v to it from what's there now. Some cut off the converter's plug and wire the cord to the OEM 120v. Or use a nearby 120v receptacle, whatever.

Check out boat and Rv which usually has lower prices than best converter for those PowerMax converters, but not always in stock. He has lots now:

Thanks for the advice, I will take a look at those. I like the idea of having something built in that is east to access, but with no easy way to adjust, it defeats the purpose!!

microlite_mike wrote:
For all practical purposes you are changing from a 55 amp converter/charger to a 55 amp converter/charger and charging speed won't change.

Incorrect - Going from single stage to multistage converter (even if both are at 55amp) will make a massive difference. It will charge considerably faster and will also prolong battery life through having a proper trickle and desulfation. I think I have unknowingly cooked my batteries a bunch at 13.6!

bobbo wrote:
Since the WFCO is famous for not going into boost mode, any other quality brand of 55 amp converter definitely will charge your batteries faster. My personal preference is Progressive Dynamics.

Thanks, I will take a look at them!

Since the WFCO is famous for not going into boost mode, any other quality brand of 55 amp converter definitely will charge your batteries faster. My personal preference is Progressive Dynamics.

When off grid using generator recharge, you do 50-80s or maybe 50-90s with FLA. So it can be that there is little time advantage with LFP---very scenario dependent.

My ugly graph has 55 amps on a 220 AH bank doing a 50-80 reach 72% SOC before amps taper. So most of the 50-80 is at constant 55 amps anyway and would take the same time with LFP--except a small diff in time where the LFP does not take as much heat loss. That heat loss only gets going with the FLA above 80% SOC as noted in the Trimetric's manual wrt charging efficiency assumptions for that monitor's AH counter.

The LFP advantage in time for the same amps is in the zone above 75% say, but the gen will not be running by then anyway. Itinerant1 does more like 35-75s with his LFPs so not much time saving there over FLA times, but he uses his LFPs for other advantages mainly.

3tons hates it when I doubt he saves much time on solar recharging like he claims he gets from no heat loss on recharging. Since solar is such a low charging rate in amps per battery bank capacity, that means the FLA will get to 90% or so before amps taper and gassing starts. If the LFPs are only going to 90% too on solar as is common it seems, they have almost the same times on low amp solar as FLAs

The LFPs can be charged way faster, but "they" forget to mention that means using way more amps and that means you need more of a generator to run the bigger amps charger--not always possible to carry in an RV.

Lots of good reasons for some to choose LFPs but recharging times are not made clear how that works in different scenarios

SirBenji wrote:
Hey folks!

I am looking at the BD 1255 MBA 55 Amp 4-Stage Main Board Replacement. I have a WFCO 8955 PEC. I am looking to upgrade to a couple Golf Cart batteries this year and we do a lot of boon dock camping so need faster charge ability when using the generator.

For all practical purposes you are changing from a 55 amp converter/charger to a 55 amp converter/charger and charging speed won't change.

It's generally accepted that a Charger for a battery bank should be at least 25% of the stated capacity of the battery bank. If you have two 6V batteries in series the average Ah capacity will be 225 ah and a Charger should deliver 56 amps minimum. Considering that this current will only be needed for the first hour or so (maybe less) changing to a larger converter/charger will yield no appreciable benefit. Lead Acid batteries charge at a .2C-.3C rate ---- period.

On a lead acid battery the charge current will taper over all the hours of charging and there isn't much that can be done to speed it up short of forcing higher currents with higher voltages and thus boiling the batteries into an early grave.

If you really want to see some short charging times, shore power or generator, go Lithium. My two LiFePo4 1000 ah batteries in parallel will recharge from 80% discharged to 100% SOC in ~3 hours.

Same depth of discharge on Lead Acid batteries will take more like 10 hours and maybe even longer to achieve float charge stage.

I am a big fan of those PowerMax LK converters (bestconverter rebrands his as in the OP) for their flexibility in choosing either automatic three stage or else choosing single stage adjustable so you can meet any battery spec but do it manually at the times required for your own scenario.

The problem with the OP lower portion type is after you install it, howinheck can you get at the setting controls???? The deck mount kind is easy. Just tuck it in under there with the side that has the two setting holes to the front so you can get at them.

On "four stage" vs "three stage" that is from some converters calling their fourth stage which comes on every so often (varies by brand how often) "equalization" when it is not. "Equalization" is an overcharge after the battery is full using say 16v to do a proper desulfation.

The "fourth stage" boost every so often to the 14.x "boost" voltage while it is in "storage" of 13.2v (third stage), is actually just to stir the electrolyte and should be called "de-stratification"

Anyway, you can get a deck mount 60 amper in there and find a way to get 120v to it from what's there now. Some cut off the converter's plug and wire the cord to the OEM 120v. Or use a nearby 120v receptacle, whatever.

Check out boat and Rv which usually has lower prices than best converter for those PowerMax converters, but not always in stock. He has lots now:

https://www.boatandrvaccessories.com/collections/rv-camper-fifth-wheels-battery-converter-chargers/products/powermax-pm3-60lk-12-volts-60-amp-power-converter-battery-charger-w-led-light

Let's see you have a 55 amp converter and want to change to a 55 amp converter to charge faster?

Wet cell batteries determine the amount of charge they will accept tapering lower and lower as the SOC goes up. It is not based on time. For “fast” charging you can’t beat Lithium. Have you compared the cost long tern between the two? Have you considered solar for charging? Much easier than running a generator. I’m charging right now…no noise, no gasoline, no maintenance.