Charge Controller Not Charging Batteries

[mconnell61]

Pull hard on all your crimps, the wires shouldn't be able to slip out. If you can pull the red wire out of those ring terminals, they aren't crimped well enough and are not making a good connection.

I checked all crimped wires and the are all very tight.

 

[sunshine_eggo]

During the mid-day sun I check the voltage input to the charger with a voltmeter and it says 134 volts.

Those are 36 cell panels. When producing maximum output, they yield about 18V. 18V * 8 = 144V if you have placed them in series.

When not producing power, they should yield about 180V. I suspect that may be too high for your controller if you see cold temps in winter.

However, when I check the output voltage of the charger it only reads 3 volts? Research tells me that it should be between 10-14 volts.

That implies you have an open circuit between your MPPT and batteries. You should measure battery voltage at the battery terminals.

I also took a voltage reading of each battery and they only read 11 volts each instead of 12.5 volts.

They are destroying themselves.

It seems like the charge controller is not charging the batteries.

Agree.

My two inverters also show green and red error lights that seem to be indicating that the batteries aren't charged enough.

44V is probably below their cut-off voltage.

On the left side of the charge controller face a green error light flashes on and off for a few seconds then stops for a short period of time, then comes back on and flashes on an off again before turning off for a while again. I checked the error codes in the controller manual and it seems like this green flashing light is indicating that the batteries are over-discharged.

It's probably not detecting a battery due to the aforementioned open circuit between the battery and MPPT.

 

[AntronX]

This is a picture of one 700 watt panel in my string of eight panels.

Looks like 100w panel. Two busbar cells are very old.

 

[robbob2112]

The grand Eggo knows his stuff...

One thing they did was list the efficiency as 30%....typical is around 20 to 22 percent, but not for flexible panels.

They just made stuff up like scammers, no basis in reality. I suspect the price was to good to be true as well. I would have guessed 50watt panels from the pictures. You were had, accept it as a learning experience and move on.


This goes in depth of how to connect your batteries together. One thing folks with a background in electrical/electronics tend to overlook is the resistance of the cables, connections, and bus bars. These really make a difference when you are doing battery systems.

S

Thread 'Calculation of parallel string battery currents'

Apr 5, 2022

Hi, everybody! I'm a retired EE. I didn't want my EE skills to fade away after retirment, so I exercise them when I can. Whenever I see a non-trivial circuit analysis problem on one of various forums I frequent, I challenge myself to solve it. Recently I watched Will's video about current sharing in a parallel battery string, and it occurred to me that the string is just a circuit. It could be solved using standard circuit analysis techniques giving theoretical values for the battery currents. I wondered if this has been done before and posted on the web. I found a link on this forum...

• Solarod
• Replies: 150
• Forum: General Battery Discussion

• 

If it were me I would take everything apart and rearrange it so it makes sense and apply what you learn from eggo and that link I listed.

 

[sunshine_eggo]

The grand Eggo knows his stuff...

One thing they did was list the efficiency as 30%....typical is around 20 to 22 percent, but not for flexible panels.

They just made stuff up like scammers, no basis in reality. I suspect the price was to good to be true as well. I would have guessed 50watt panels from the pictures. You were had, accept it as a learning experience and move on.


This goes in depth of how to connect your batteries together. One thing folks with a background in electrical/electronics tend to overlook is the resistance of the cables, connections, and bus bars. These really make a difference when you are doing battery systems.

S

Thread 'Calculation of parallel string battery currents'

Apr 5, 2022

Hi, everybody! I'm a retired EE. I didn't want my EE skills to fade away after retirment, so I exercise them when I can. Whenever I see a non-trivial circuit analysis problem on one of various forums I frequent, I challenge myself to solve it. Recently I watched Will's video about current sharing in a parallel battery string, and it occurred to me that the string is just a circuit. It could be solved using standard circuit analysis techniques giving theoretical values for the battery currents. I wondered if this has been done before and posted on the web. I found a link on this forum...

• Solarod
• Replies: 150
• Forum: General Battery Discussion

• 

If it were me I would take everything apart and rearrange it so it makes sense and apply what you learn from eggo and that link I listed.

That's a beastly link.

 

[robbob2112]

That's a beastly link.

I know, it is a fun read all the way to the end, especially if you work the math with it as you go.

Kinda cruel to assault a new person with it... maybe call it tough love since the OP seems to be in denial...

But most people skip it and just do things the easy way which works pretty well.

 

[sunshine_eggo]

I know, it is a fun read all the way to the end, especially if you work the math with it as you go.

Kinda cruel to assault a new person with it... maybe call it tough love since the OP seems to be in denial...

But most people skip it and just do things the easy way which works pretty well.

Even if he can just understand how much wiring influences current from this...



It's a big win...

 

[pollenface]

My first mppt was a $13 single stage pwm with an mppt sticker on it. I hooked it up to two 50ah LFPs for 29.2v all day every day until they lost all their capacity.

That was a great lesson.

 

[robbob2112]

I checked all crimped wires and the are all very tight.

Your crimps look not good. Lots of exposed cable and the crimp appears to be just layed on concrete and hammered. Looks like you need to invest in a good Temco crimper or buy pre-made cables.