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Rocky_3's avatar
Rocky_3
Explorer
Aug 28, 2015

Replacing WFCO 65amp converter

Replacing failed WFCO 65amp power converter. What do think is the better replacement.
PowerMax PM4B-75 (75 Amp 4-Stage Converter/Charger)
The power max has a 3 year warranty
PD 9270C 70 Amp RV Converter/Charger
The Progressive Dynamics has a 2 year warranty.

2011 Montana High country
  • I have had two PDs on different TTs, and now on my present TT the powermax which replaced the WFCO it came with.

    For my use, I like the powermax better, Even though it is only 55 amps vs the larger PDs and WFCOs I have had. It seems to do a better job in float. Note that I am in Phoenix AZ, where temps in the 110 degree range are common. Both the PDs and the WFCOs held a higher voltage in float and water use was higher in the batteries.
    The PM definantly lets you know when it changes modes. It is like a manual transmission shifting gears. My PDs were seamless in that regard. My WFCO rarely if ever changed modes.
  • smkettner wrote:
    How many batteries? Do you expect a fast charge to minimize generator time?
    Any special high draw 12v load to need more than 40 amps or even 60? (such as tank heaters)

    I don't really recommend PowerMax as it does not hold absorption voltage and leaves you slow charging at 70%+.


    Correct, but the choice against the PD is lower than rated amps and tapered too for the Bulk Stage, or get full rated bulk and then low amps for absorption. You would have to time each for how far past Bulk you want to run the gen. Don't forget the the percentage of SOC Bulk stops depends on the charging rate (charging amps vs AH of battery bank) so a lower rate will get you to a higher SOC anyway (but take longer)

    All about scenario. EG. use the Bulk to get to there and solar after that. Or are you usually on shore power? Scenario, scenario.

    Or, you can get the PowerMax variable voltage version and do it yourself how you like if you are are a "hands on" kind of guy.

    That is why I said "other considerations" may apply. You have lots of choices if you are willing to adapt your camping style for charging, but few choices if you are not a "hands-on" kind of guy.

    BTW there is no shame in not being a "hands on kind of guy" for Rving, especially if retired. Your area of expertise from when working may not include how to do the tricky bits when Rving. That does not make you a bad person! Just might take more out of your wallet till you get up to speed.
  • I too have run the PDs for over 15 yrs w/ never a problem. You will not find a converter that will make batteries last longer, while needing very little electrolyte (water) replacement, not to even mention fast charging.
  • How many batteries? Do you expect a fast charge to minimize generator time?
    Any special high draw 12v load to need more than 40 amps or even 60? (such as tank heaters)

    I don't really recommend PowerMax as it does not hold absorption voltage and leaves you slow charging at 70%+.
  • I've really liked the Progressive (with charge wizard) I've had in the last two rigs, totaling over 10 years of use.
  • The PowerMax 75 has power factor correction so it can run on a 15a circuit, which the others don't have, and is needed above about 60amps DC charging or you must go to a 20a circuit. (affects which Honda size will run it too)

    PowerMax has a two year warranty, but Randy at bestconverters offers a 3 year on his versions of the standard PowerMax unit which he has modified a little (14.6 instead of 14.4 etc--compare their specs)

    No way to answer your main question without knowing how long of a generator time you think is acceptable to do a "50-90" on your size (what?) battery bank. Each converter has its pros and cons depending on your camping lifestyle.

    I would choose the 75 PF corrected over the 60 non PF to get more amps with the same 15amp circuit, but you may have other factors to consider, no idea.

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