Forum Discussion
MEXICOWANDERER
Aug 16, 2014Explorer
BFL13 wrote:
Sounds like you need to equalize the heck out of those batteries and start over. Meanwhile
The PM 75 amper will take the batteries up to 14.6v then the converter drops to 13.6v and stays there while amps taper. With 75 amps on a 430AH bank, that is a 17% charging rate, so expect your SOC when reaching 14.6 to be about 78% Now you have to get from 78-100 with a Vabs of 13.6. This will take a very long time (two days? I don't know when it drops to 13.2, but not for a while.
Even then you will not be getting the batts to 100% since that takes a Vabs of more like 15v, which converters don't do. So you really need two chargers. One that can get the batts to 15+ volts and also your converter to supply 12v (13.6) on shore power. I use a VEC1093DBD for charging to 100% and then doing an overcharge/equalize before leaving the batts on the converter for their Float.
BTW having the batts under the bed is ok if they are in properly sealed battery boxes vented to the outside. A lot of those boxes have their lids not down tight because the battery cables are not placed properly.
REAR WHEEL
A cheater is to fit one of those MEANIE WONKA 33 amp chargers into the system. Learn what it does for amperage output when the Gizmo2000UltraHyperSonic converter is lying it's fool head off, as found with a hydrometer. Set the MW to 14.6 volts. The ammeter is going to react Mamma, Poppa or Baby bear as far as amperage is concerned when the MW is put on line when the converter is near the end of it's absorbsion charge stage
Example
26.3 amps LIE! batteries are undercharged
5.4 amps BINGO!
0.0 amps LIE! Check for overcharging
All with the flip of a switch.
You have to do your own "Trends and Tendencies" workup for what amperage is correct for your battery bank using a hydrometer for calibration.
And you get a charger fix in the process. Use a spring wound timer on the MeanWell.
"Smart Charger" is about as insane a term as "Compassionate Overkill"
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