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Low charge current, normal voltage?

Bowlegs868

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I have a system of four 350W panels (40.2V, 8.7A) in a 2S2P config... my 35A charge controller reads the incoming array voltage at 80+V which I expect but the amps barely hits 2A when charging a single 12V 105Ah battery... is this normal/ok?
 
I have a system of four 350W panels (40.2V, 8.7A) in a 2S2P config... my 35A charge controller reads the incoming array voltage at 80+V which I expect but the amps barely hits 2A when charging a single 12V 105Ah battery.
Do keep in mind that a 35A SCC on a 12V system can only support about 490W of solar panels. You have 1400W. That's some serious over paneling. I wouldn't use more than two of those panels with that SCC at 12V.
 
Is the battery depleted? What is the charging voltage set point? What battery chemistry?
If a load is added, say 10 amps, does the amps from the controller increase?
 
Do keep in mind that a 35A SCC on a 12V system can only support about 490W of solar panels. You have 1400W. That's some serious over paneling. I wouldn't use more than two of those panels with that SCC at 12V.
ohhh! the more you know

thanks for that... that original system started with 6 batteries but due to some "bad luck" I'm now temporarily on a single 12V
 
Is the battery depleted? What is the charging voltage set point? What battery chemistry?
If a load is added, say 10 amps, does the amps from the controller increase?
the battery is fairly high by the time recharging begins but seeing the voltages as high as it should be and then seeing the amps so low, it got my attention... (ps. am fairly new to the electrics world)

(see attachment for charge voltages)

it's an AGM battery

I will test the load out and see what happens
 

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that original system started with 6 batteries but due to some "bad luck" I'm now temporarily on a single 12V
The number of batteries is irrelevant. It's the system voltage. Whether you have 1 12V battery or 6 12V batteries all in parallel it is still only 12V. The SCC can only handle so much wattage at a given voltage.

If your 6 batteries were wired in 2S3P for a 24V system then that's different because it is a higher voltage. Twice the voltage means twice the wattage for a given amperage.
 
The number of batteries is irrelevant. It's the system voltage. Whether you have 1 12V battery or 6 12V batteries all in parallel it is still only 12V. The SCC can only handle so much wattage at a given voltage.

If your 6 batteries were wired in 2S3P for a 24V system then that's different because it is a higher voltage. Twice the voltage means twice the wattage for a given amperage.
yeah my mistake for not mentioning it then but that was the case... 6 batteries wired for 24V
 
The SCC is probably noting a close to fully charged battery.

Also even a fully depleted 105ah AGM battery, 30a is quite a bit of charging current, and my guess is over the specifications of a single unit.

When you were running multiple batteries, what sort of current were you seeing from the SCC?
 
The SCC is probably noting a close to fully charged battery.

Also even a fully depleted 105ah AGM battery, 30a is quite a bit of charging current, and my guess is over the specifications of a single unit.

When you were running multiple batteries, what sort of current were you seeing from the SCC?
was kinda hard to know what it was exactly since the SCC was a PWM but the readings were higher — both PV and battery amp readings were always the same hence the reason why I couldn't tell what was really going on
 
I wouldn’t worry about anything until you have a low/dead battery and trying to charge it.
 
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