Many battery manufacturers indicate that LFP does not need to be floated. That is true if you're just placing them in storage. However, when using them in cyclic power system, a float voltage is needed so the MPPTs provide solar for loads trying to pull the battery voltage down.
Set float voltage to 3.4V/cell, 54.4V.
SoC curve will look like this:
Given that you are only achieving 90% SoC, you may wish to review how you're charging the battery.
Are you using ESS?
You should not discharge the battery to 0% SOC (at least not when grid is available). If that really is 0%.
thank you so much for your answers. Yes I think ESS is what I use. I was told that as batteries were lithium, discharging them to 0% was not an issue.
Any idea why batteries don't reach 100%?
Please post the settings of the MPPTs and multiplus.
While lithium batteries can be discharged to zero, doing so often will reduce their lifespan. If you are using ESS, in your ColorControl GX you have a setting named "Minimum SOC (unless grid fails)", which apparently is set to 0%. Increase that to at least 10% (or, even better, to 20%). But you should also check the battery voltage and cell voltages, especially when the battery is (close to) empty and when it is full.
I would love to, but I'm the final user, I have no idea how to reach that, it has been set by the dealer.
Either ask these questions to your dealer or start by reading the manuals of all your components (and after that you should be able to post the settings).
If those VCSF files contain the actual config of your MPPT, your installer did NOT set your MPPT appropriately at all, especially for Lithium.
You need to IMMEDIATLY DISABLE temperature compensation.
Revise BOTH as follows:
If you have a BMV-712, please upload it's configuration.
I've drawn vertical lines to find the same time on each chart. Your voltage is mostly constant (blue line), and the current is mostly constant (orange line), though it does appear the current is slightly negative. This doesn't make a lot of sense.
You do indeed appear to be losing that ~5% SoC even with available solar.
This is likely a calibration or configuration issue, and it shouldn't be like this. You should contact your installer to have them resolve it. It's not working as it should, and they should fix it.
If you are using ESS, then the MPPTs are controlled by the Multiplus.
It's still good to have the MPPTs configured properly for your battery, but as long as ESS works as it should, these settings will be ignored (except the charge current).
As I said, if you have to change the settings, first read the manuals.
thank you all, so everyone here feels there must be something wrong in the configuration of the installation, right?
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