diy solar

diy solar

Battery configuration for AGM batteries in series/parallel

Ignore the SOC readings they are only based on voltage and thus inacurate.

Once the solar had gone to bed, the 25.95 volts, almost 13 volts per battery, is about right for a charged AGM.

Set the Equalise duration to zero.

Noise from the battery seems odd. Try the charge ( boost) volts at the slightly lower setting 14.4 x2 , 28.8 volts.

If you are following the charge process, ( assume the battery pack has been discharged), the voltage should rise to the charge target, 29.2 or 28.8 , whatever was set, hold this for two hours with gradually falling current, then drop to float volts, 27.6 volts.
There must be enough solar for this, solar Input volts needs to be a few volts higher than battery volts.

As discussed, ignore the battery SOC, its incorrect.

Mike
 
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Ignore the SOC readings they are only based on voltage and thus inacurate.

Once the solar had gone to bed, the 25.95 volts, almost 13 volts per battery, is about right for a charged AGM.

Set the Equalise duration to zero.

Noise from the battery seems odd. Try the charge ( boost) volts at the slightly lower setting 14.4 x2 , 28.8 volts.

If you are following the charge process, ( assume the battery pack has been discharged), the voltage should rise to the charge target, 29.2 or 28.8 , whatever was set, hold this for two hours with gradually falling current, then drop to float volts, 27.6 volts.
There must be enough solar for this, solar Input volts needs to be a few volts higher than battery volts.

As discussed, ignore the battery SOC, its incorrect.

Mike
Ok thats helpful thanks.
I've left the breaker off until I'm back to monitor things so it doesn't do anything silly when I'm away.
From the research I've done. 14.6V should be ok. But I will lower it slightly as you say.

According to this link, its OK if they make a gentle bubbling and voltages are within the limits. It sounded more like a can of soda bubbling and not as vigorous as what my existing flooded cells do.

Anyway, it looked like it was putting in around 10A or so and charged the bank within 2 hours if that's the case. The batteries were showing a 60% charge from new.
I dont believe they charge them at the factory or else it reduces their shelf life until they get to their destination because they regularly need topping up or so I've heard.
 
I noticed my app was reporting a slightly higher voltage than I specified yesterday. Need to check against it with my multimeter, but its showing 29.3V on the display when it should be no more than 29.2V.
The bubbling noise had me a little concerned, but others saying here it's OK. The batteries are definitely full. Will the controller keep running on boot charge for the first 180mins at this voltage, or does it slowly drop down?
 
I noticed my app was reporting a slightly higher voltage than I specified yesterday. Need to check against it with my multimeter, but its showing 29.3V on the display when it should be no more than 29.2V.
The bubbling noise had me a little concerned, but others saying here it's OK. The batteries are definitely full. Will the controller keep running on boot charge for the first 180mins at this voltage, or does it slowly drop down?
Screenshot_20220626-143710_EPEVER Pair.jpg
So I'm getting about 29.8V currently. I'm concerned this could be too high. Multimeter is confirming the same voltage across the bank.
While charging, the battery voltages all vary slightly. They are climbing up after a few mins and is now showing 29.8v across the bank with my multimeter. Battery voltages is varying between each battery. One reads about 15v and others are around 14.8v each or so. I'm thinking I should drop the voltage on the controller perhaps to 28.8v?
 
Voltage is now dropping off slightly on its own.
Each battery reads 14.75v, the next 14.29v, 13.59v and 15.6v.

This is while charging, currently across the bank I get 29.5v.
I dont know if measuring while charging affects readings.
 
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