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Victron 100/50 always in bulk

Cory

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I have five 100w 12v panels, three SOK 100ah batteries, a Victron 100/50 controller and a Victron SmartShunt on the way.

I installed the new controller and the SOKs last Wednesday. The controller has been in bulk mode since then. I'm in the SW Arizona desert for the winter and have used very little energy. Typically 8 to 16 ah over nights. I have attached some screen shoots of my VictronConnect app and one solar panel decal for reference.

When I installed the SOKs, two were at 12.4v and one was at 12.5v. I thought that was close enough. What am I not seeing?
 

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Did you connect these batteries to load while Victron mppt charging your batteries?
 
First issue is 21.6 volts open circuit * 5 panels is greater than the 100 volt maximum input on that solar charge controller.
Second, you have 300 amp hours worth batteries that probably arrived to you and 30 or 40% state of charge. Did you charge them all up before connecting them? If not then you have more than 150 amp hours worth of charge that needs to go into them minus any current loads.
 
Start by setting up your charge controller for LiFePO₄ batteries. Go to the battery settings screen (the one in your posted screenshot) and go to "Battery preset". Tap on drop down and select "Select preset" from the list. Then select "Lithium Iron Phosphate (LiFePO4)" from the battery presets. You can then tweak the Absorption and Float voltages as desired.

Also make sure you have the latest VictronConnect and the latest firmware on your 100/50.

When I installed the SOKs, two were at 12.4v and one was at 12.5v.
Those are really low and need to be fully charged.

Getting the SmartShunt will help but only after you are able to get the batteries fully charged at least once. Do you have a 12V LiFePO₄-friendly battery charger? It may help to fully charge each of the 3 batteries and then hook them all up in your system.

3 12.8V 100Ah batteries is 3840Wh. You were at about 12% with 12.4V. So you needed to charge 88%. That's 3379Wh. Let's say you average 12Ah per night. At 12.5V that's 150Wh. Over 8 nights that's 1200Wh. So you need 4579Wh to fully charge the batteries and replace the nightly loads. But there's no mention of your daytime loads. Your panels have put out 8kWh in 8 days. You need 4.6kWh. So if your 8 day daytime usage is more than 3.4kWh (an average of about 34Ah per day) then you are still in bulk because the batteries are still not fully charged yet.
 
The SOK battery specs state a recommended charge voltage of 14.6V. Though I charge mine at 14.2V (actually 28.4V since I have 2 in series).
Thanks, once in float, I will change it to 14.4.
 
First issue is 21.6 volts open circuit * 5 panels is greater than the 100 volt maximum input on that solar charge controller.
Second, you have 300 amp hours worth batteries that probably arrived to you and 30 or 40% state of charge. Did you charge them all up before connecting them? If not then you have more than 150 amp hours worth of charge that needs to go into them minus any current loads.
There hooked in parallel. Really!
 
Start by setting up your charge controller for LiFePO₄ batteries. Go to the battery settings screen (the one in your posted screenshot) and go to "Battery preset". Tap on drop down and select "Select preset" from the list. Then select "Lithium Iron Phosphate (LiFePO4)" from the battery presets. You can then tweak the Absorption and Float voltages as desired.

Also make sure you have the latest VictronConnect and the latest firmware on your 100/50.


Those are really low and need to be fully charged.

Getting the SmartShunt will help but only after you are able to get the batteries fully charged at least once. Do you have a 12V LiFePO₄-friendly battery charger? It may help to fully charge each of the 3 batteries and then hook them all up in your system.

3 12.8V 100Ah batteries is 3840Wh. You were at about 12% with 12.4V. So you needed to charge 88%. That's 3379Wh. Let's say you average 12Ah per night. At 12.5V that's 150Wh. Over 8 nights that's 1200Wh. So you need 4579Wh to fully charge the batteries and replace the nightly loads. But there's no mention of your daytime loads. Your panels have put out 8kWh in 8 days. You need 4.6kWh. So if your 8 day daytime usage is more than 3.4kWh (an average of about 34Ah per day) then you are still in bulk because the batteries are still not fully charged yet.
I have never calculated wh (64). I just used oped circuit volts. I can see the advantage, but would require some calculation for me. Probably not going to happen. Take a voltage reading and go out and enjoy life.
 
12.4 and 12.5 were open circuit volts.
Huh? You stated that those were the two battery voltages. That has nothing to do with the solar panels.

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That chart you posted is not for LiFePO₄.

I have never calculated wh (64). I just used oped circuit volts. I can see the advantage, but would require some calculation for me. Probably not going to happen. Take a voltage reading and go out and enjoy life.
I have no idea what you mean. It seems you missed all of the important information I posted earlier. All the math I did is mostly unimportant. It was there for completeness to explain your issue. But setting up the SCC battery settings correctly in VictronConnect is very important. You have it wrong. Fully charging your batteries with a charger before first use is extremely helpful to resolve your issue.

In a nutshell you asked why it was in bulk all of the time. It's because you started with empty batteries and your solar is too weak to keep up with your current loads and fully recharge the battery at the same time. Even once you get them fully charged, overnight power usage will use up some of the battery. The next day when the solar kicks in it will go into bulk charge to recharge the battery. That's normal.
 
First issue is 21.6 volts open circuit * 5 panels is greater than the 100 volt maximum input on that solar charge controller.
Second, you have 300 amp hours worth batteries that probably arrived to you and 30 or 40% state of charge. Did you charge them all up before connecting them? If not then you have more than 150 amp hours worth of charge that needs to go into them minus any current loads.

According to the third image in the original post, it looks like the produced PV Vmax is around 21 volts. The panels must be wired in parallel, not series.
 
The sequence of max and min battery voltages by day is progressing exactly as you would expect. You are putting in somewhat more than you are using, but you had a big deficit to overcome. Given you got to 13.59v yesterday morning ( just at the edge of the knee) I assume at the end of the day you got basically full. Given you set float at 13.4 it will probably transition back into bulk everyday. If you don’t really need a full charge every day your batteries will last longer if you set float down to 13.2 ( the Victron recommendation for LFP).
 
The sequence of max and min battery voltages by day is progressing exactly as you would expect. You are putting in somewhat more than you are using, but you had a big deficit to overcome. Given you got to 13.59v yesterday morning ( just at the edge of the knee) I assume at the end of the day you got basically full. Given you set float at 13.4 it will probably transition back into bulk everyday. If you don’t really need a full charge every day your batteries will last longer if you set float down to 13.2 ( the Victron recommendation for LFP).
Yup, good eyes. At 64, that fell through the cracks.

I have been checking the graph every morning over coffee. That will give me a "feel" for the system.
 
Latest info, it's floating every day now. Lowered float voltage from 13.4 to 13.2. I was reminded lith doesn't need to be topped off every day. I had lead acid a long time.

I will start looking for a lith charger for the tin can; it's our boondocking converted aluminum cargo trailer. Would anyone have any recommendations from prior experience? I have had a couple of Progressive Dynamics chargers over the years that worked well and were reliable.
 

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It seems you still haven't setup your SCC for LiFePO₄ yet as I mentioned in post #4.
 
It seems you still haven't setup your SCC for LiFePO₄ yet as I mentioned in post #4.

It might be. As I recall, if I selected the LiFePO4 setting in Victron Connect, but then tweaked the settings, it then changed the Battery preset value to "User Defined". But it's been a while since I did the initial setup.
 
It might be. As I recall, if I selected the LiFePO4 setting in Victron Connect, but then tweaked the settings, it then changed the Battery preset value to "User Defined".

Yes, even if LiFePO₄ is first selected but then you tweak a voltage, for example, it does show "User Defined". But I don't think that LiFePO₄ has been selected because when you do it looks a lot different. For example, the "Equalization voltage" is grayed out and shows "Disabled". The OP's screenshot shows that value as still active. There are a few other changes that I see in my SCC battery settings compared to the OP's screenshot.
 
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