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What to use to see actual battery power available. Clearly charge controller not an indicator

Justjeanne1

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So, based on advise from this forum, I have added more solar panels, but also had to add another charge controller because these are limited to only 540w input. I put this array of panels on the opposite side of the building which gets sun in the morning. As you can see, the new panels and new charge controller are at 100%, while the orig setup is only at 94%. Both charge controllers are tied to the same bank. So, based on these readings, the charge controller is not telling me what the batteries are storing, but instead are telling me how much sun is hitting the solar panels. What do I need to see how much storage I have in my battery bank?

thank you
 

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I use a Victron shunt and BMV-712 to monitor the state of charge, as well as the total charge going to or coming from the battery from multiple sources or loads. There are other options, but this works well and is accessible via Bluetooth to check on a phone app which provides current and historical info.
 
I use a Victron shunt and BMV-712 to monitor the state of charge, as well as the total charge going to or coming from the battery from multiple sources or loads. There are other options, but this works well and is accessible via Bluetooth to check on a phone app which provides current and historical info.
Thank you Rick, I will order those.
I don't know what sort of quality renogy is, but they have a nice smart monitor that shows a lot of info plus <$100:

I have all kinds of Renogy products including the BT-1 wireless monitor, but they are no help and you get stuck on hold for hours, then they tell you that you Can’t connect 2 mppt charge controllers to the same bank. And maybe you can’t, but i Was told that it is possible, and watched a video on how to do it. I am just not sure why they are reading different. I just plugged in my minifridge to test, and one charge controller went down, and one stayed at 100%. This shit is confusing and not logic to me. Uggh
 
The renogy has a lot of info on the display, BUT the Victron has an app which puts the display on your phone which is VERY handy.

Can the Victron be set to show and maintain SOC reading on the meter?
 
Thank you Rick, I will order those.
I have the BMV-712 also and its nice.
I have all kinds of Renogy products including the BT-1 wireless monitor, but they are no help and you get stuck on hold for hours, then they tell you that you Can’t connect 2 mppt charge controllers to the same bank.
I have three Victron MPPTs connected to charge my batteries. Another user says he's mixed MPPTs and PWMs together to charge a battery bank. My Victron MPPTs are networked together so they can work together, but how it does it is a mystery to me. The manual says little more than how to create a network. If MPPTs and PWMs can be mixed and matched, than this may not be needed.
 
I have the BMV-712 also and its nice.

I have three Victron MPPTs connected to charge my batteries. Another user says he's mixed MPPTs and PWMs together to charge a battery bank. My Victron MPPTs are networked together so they can work together, but how it does it is a mystery to me. The manual says little more than how to create a network. If MPPTs and PWMs can be mixed and matched, than this may not be needed.
I do not have my mmpt’s networked together, I have one on one charging positive on battery #1 and negative on battery#4, and the other is opposite. Positive on battery #4, and negative on battery #1. The positivr to the inverter coming from battery#1 and the negative coming from battery #4. Is this correct?
 
I do not have my mmpt’s networked together, I have one on one charging positive on battery #1 and negative on battery#4, and the other is opposite. Positive on battery #4, and negative on battery #1. The positivr to the inverter coming from battery#1 and the negative coming from battery #4. Is this correct?
I'm not sure what the networking does, but it is in the app. I do know that when I turn one charger to equalize, they all go to equalize.

I'm not sure of your battery setup. I don't hook them directly to the batteries, I do this through the busbar like this:
1628183864795.png
The negative busbar has all the same connections.
 
Can the Victron be set to show and maintain SOC reading on the meter?
Based on the settings you enter, the BMV-712 will sync at 100% charge and base SOC from use vs capacity. You can also see voltage, which can give you some idea as a double-check. The monitor re-syncs at each 100% charge capacity it senses, and will show time since last sync, and number of synchronizations… handy info to know!
 
I'm not sure what the networking does, but it is in the app. I do know that when I turn one charger to equalize, they all go to equalize.

I'm not sure of your battery setup. I don't hook them directly to the batteries, I do this through the busbar like this:
View attachment 58954
The negative busbar has all the same connections.
Can you send me a picture?
 
I don't know what sort of quality renogy is, but they have a nice smart monitor that shows a lot of info plus <$100:

Just picked one of those up on sale. Seems to work well. The Renogy coupon code "empowered" should help if you go directly through Renogy.

Amazon is great because you can return Renogy products no questions asked. Renogy themselves seem not to like returns, or answering phones. Make sure you use a credit card, just in case. ?
 
What batteries do you have? With a little interpretation lead-acid can be judged by battery voltage. LFP often has a BMS that gives a decent state of charge reading. If perfect accuracy is needed your battery might be too small.
 
Can you send me a picture?
Here is a bad angled shot of it finished off:
1628199997103.png
One SCC is behind the Powerboard, and two more SCC's are located on a separate power board. All three SCC's are connected with 6 AWG wire and attached to the busbar on 5/16th studs.

With my 24 volt conversion, I have two more wires to put on one empty stud. One would be the 24 volt to 12 volt 70 amp converter. The other would be the 120 VAC to 24 volt Charger.
 

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