My Screwy 31
First off let me say I am not stressing over this. It's just a battery, it is only money, it is meeting my overnight needs, but it is displaying strange behavior, and I am curious as to why. So th...
Forum Discussion
landyacht318 wrote:
Well for now I'll Use up the 31 and see how that goes. I cannot fit T 105s or any GC-2 due to height, and I think the T- 1275 is also a bit tall for either location I have available.
I'm also trying to meet minimum bulk current recommendations via solar only, so I am not looking to increase capacity, and I can't realistically put any more solar on my roof.
Right now the 31 just barely allows the hood to close, and the AGM 27 looks lonely in the battery box that 2- 27s can fit within.
Last night I only took 26 amp hours from the 31 and at some point it dropped in the 12.1v range Likely when I plugged in the depleted laptop while the fridge condenser was running.
Right now 6.6 solar amps are holding it at 14.4v, and once this tapers to ~0.8 amps I have a 15.3 volt float/ finish programmed.
I'd bump that bulk charge rate from 14.4V to 15.0V, and then finish charge at 14.4v. You are drawing constantly on the 31 while charging, are you not? So that 6.6 amps is misleading as to what actually is going into the battery without a draw against it? You need that 15.0 volts to force those amps into that big group 31 battery, to get it to near 100% with stuff running off of it.
I just don't think, with the voltage you lose and the amp hours overnight, that you are ever getting enough charge, either replacement amps, or voltage, to get it up to where it needs to be to be topped off. Something keeps drawing it down constantly.
Forget about getting it down to .6 Amps, that's wasting wattage on your solar unit... keep that voltage up so that it keeps the amps up on that battery... Something tells me it has a lot of internal resistance, for one reason or another.
Is there a way to top off your laptop while your solar panel is still generating enough amps to cover what it draws, say sometime after 2 or 3 pm? Do you have a smaller inverter to run just to charge the laptop, or something that bucks the voltage from 12.0v to whatever you need for charging you laptop, instead of up to 120V, then back down to 17 or 18V?
