Forum Discussion

Grodyman's avatar
Grodyman
Explorer
Aug 05, 2019

Battery Charging

So I went on a 3 day trip and charged on the 3rd day by plugging the shore cord into the Honda 2000 and also putting a dumb automotive charger on the terminals.

I used the 10 amp setting, and with the onboard converter got about 20 amps of charging current into the batteries according to the battery monitor.

For some reason, the 50 amp (jump start) setting didn't work, the needle gauge started to jump all over the place. Switch back to 10 amp setting and things were great.

Anybody know why the 50 amp setting wouldn't work to charge dual 12v batteries?

Gman
  • 50 amp is a start/boost mode only good for maybe 30 seconds to help crank the starter.

    You would probably be better served to swap the converter... post the model number for best suggestions.
  • The 50amp jumpstart feature might have been confused by the onboard converter output.

    The charger's clamps might have been going intermittent at 50 amps too, due to too little surface area/bad connection.

    In addition to posting the current converter number. State how much battery capacity you have and what type of battery.
  • The battery accepts the amps from the charger and from the converter in proportion to the spread between the battery's voltage and the charger's voltage and the spread between battery and converter voltages.

    Say the battery is 12.3v and the converter is 13.8v, while the charger is 14.4v. When the two chargers are turned on, now the battery voltage goes to 13.3v, leaving a spread of only 0.5v for converter and 1.1v for charger.

    The charger does its full 10 amps and you are only getting 10 amps from the converter instead of what it is rated for (35? 45?). As battery voltage rises during recharge the spread to 13.8 gets smaller and the converter's amps taper to zero, leaving the charger doing its 10 amps. Later as battery voltage rises further towards 14.4, the 10 amps will taper down too until the battery is full.

    What you want is a converter that will do 14.4 instead of 13.8 so you get full converter amps to the battery, which will be more than 20. Then the charger's 10 amps can be on top of that.

    You want both chargers to be nearly the same voltage for them to add their amps all the way through the recharge.
  • Interesting. My Wfco converter takes too long to charge on generator. I have 2group 24 12 v batteries. Short of replacing with a progressive dynamics converter, I’m looking for a fast way to charge on generator.

    Maybe solar is the answer.
  • Those HF automatic chargers are the epitome of solid snot. I salvage what I can from them. Most folks on this forum aren't heavu duty techies so I'll try and make this simple.

    They use a flat sheet of 11 gauge aluminum doe the button diode heatsink. Then they attempt to retain a pair of button diodes by scrap metal spring tension to hold the diodes against the aluminum. Won't work can't work the principle is absurd.

    OK down to business...

    The mickey mouse 39 cent circuit board "automatic charger" sees the ripple in any parallel charger and throws a hissy fit. I tried caps to smooooooooth out the ripple but the sensor circuit detects the new capacitor and limits the charge voltage as being high which throttles current way back..

    Neat huh?
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    WFCO most common failure is to fail to go into BOOST

    Someone dissected one and found a single part Easily replaced (A resistor as I recall that was the culprit but I did not bookmark the thread Do not know if was in these forums or IRV2 and I no longer play on IRV2.

    My best suggestion is progressive Dynamics 4600 if it's part of the power panel or 9200 for stand alones.

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