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Lifepo4 48v batt running down

It's not a comms thing.
A BMS doesn't wake up the SCC.
It just limits the charging current, when the battery gets close (~90%) to full.
And sends battery SOC % to the AIO.
Mine acts the same way with or without closed loop. (For this issue)
 
And sends battery SOC % to the AIO.
Bingo.

The SCC should wake the battery up when it sees enough voltage, for you know, charging.

Imagine having to manually turn on the inverter every morning, missing generation if you got up at 9am instead of 6am.

Makes no sense whatsoever, and is not how these devices are intended to run. They are designed for automated use.

Like mine operates with the switch in the off position, it charges the battery EVERY SINGLE MORNING it sees PV voltage, regardless of battery percentage.

Again, the switch is off.

Battery is charging.

It does it if the battery is at 5%. It also turns on if the battery is at 99%. If the battery is at 100%, it also turns on!
 
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The SCC should wake the battery up when it sees enough voltage, for you know, charging.
It doesn't have dark start capability.
But that's not what this conversation is about, anyway.
It's about the SCC starting up in the morning. Which I believe was addressed in a later firmware.
I was looking for one of the old threads about it, but couldn't find one.
It's been so long, I don't even remember which members had the issue.
I just remember testing mine, and confirming it was the same.
I didn't follow the thread very long, because it didn't affect me.
 
It doesn't have dark start capability.
No idea what you mean by this. It won't start without solar voltage, that's obvious.

But it will start up in the off position and charge the battery, again irrespective of battery charge status, or float from the previous day.

It also does start if it's "dark" outside, as long as the PV voltage is over 120v, 0 amps doesn't matter.
It's about the SCC starting up in the morning.

It does start up in the morning lol.

In the off position.

It starts charging the battery.

Just because yours doesn't do this, as you're not using comms, doesn't mean it doesn't operate like this...
 
Winter is the same, here.
It's been 3 months since solar got me to 100% charge. But I should get there, today or tomorrow. And then I'll be fine until some time in November, again.
Only because you got complacent and didn't hook up the rest of your panels, getting distacted by tapping condensate for your toilets. . . My hero!
 
Ah crap, no BMS communication with the inverter then.

So, which mode you use? USE or US2 mode?

USE = there is float, however the battery voltage needs to be 2v lower than your set float voltage, otherwise, there will be no solar recharging next day.

US2 = no float, when battery voltage reach CV value, it stops charging immediately.
I'm using USE. I'll switch to USE 2 to see what happens. For the moment anyways.
 
Bingo.

The SCC should wake the battery up when it sees enough voltage, for you know, charging.

Imagine having to manually turn on the inverter every morning, missing generation if you got up at 9am instead of 6am.

Makes no sense whatsoever, and is not how these devices are intended to run. They are designed for automated use.

Like mine operates with the switch in the off position, it charges the battery EVERY SINGLE MORNING it sees PV voltage, regardless of battery percentage.

Again, the switch is off.

Battery is charging.

It does it if the battery is at 5%. It also turns on if the battery is at 99%. If the battery is at 100%, it also turns on!
I assume if your battery is at 100% when it turns on it just balance charges and doesn't charge over 100%?
 
So I'm at the farm, The battery was at 40% because I ran the generator before I left the other day. Inverter off and no charging. It was sunny when I arrived. Batteries not charging or discharging. So I switched the inverter on,the charging started then I switched the inverter off. Charging continued but when it went from sunny to cloudy it went from charging 23 amps to discharging a couple of amps. I can imagine this could drain the batteries as some days if it charges at 25 amps for half an hour then gets cloudy and discharges at 3 amps it could empty the battery. It can be cloudy here for days with little sun.
 

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Ok update, when the clouds come it stops charging and when the sun come out again it just discharges at 0.6 amp. It doesnt charge again until the inverter is switched on and then stops charging even if the sun is put after a while.
 
I assume if your battery is at 100% when it turns on it just balance charges and doesn't charge over 100%?
Yes.
Ok update, when the clouds come it stops charging and when the sun come out again it just discharges at 0.6 amp. It doesnt charge again until the inverter is switched on and then stops charging even if the sun is put after a while
That doesn't sound right at all.

Even with clouds you should have some current with over 200v of panels.

Mine gets woken with very low wattage coming in, the inverter reports single digit numbers early in the morning. As soon as solar is over the inverter draw it starts charging even if it's only 20 watts, and it will never stop charging if the loads are lower than PV production. I get hard shading for half an hour on the whole array but somehow it's still charging at 150-200 watts through that time too.

I have less panels than you so your current coming in the morning should be plenty. It should charge your battery any time pv production is higher than loads, if not something is wrong.
 
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Yes.

That doesn't sound right at all.

Even with clouds you should have some current with over 200v of panels.

Mine gets woken with very low wattage coming in, the inverter reports single digit numbers early in the morning. As soon as solar is over the inverter draw it starts charging even if it's only 20 watts, and it will never stop charging if the loads are lower than PV production. I get hard shading for half an hour on the whole array but somehow it's still charging at 150-200 watts through that time too.

I have less panels than you so your current coming in the morning should be plenty. It should charge your battery any time pv production is higher than loads, if not something is wrong.
I think changing from US2 to USE fixed the problem of not charging. We'll see if it wakes itself up in the morning. My head is fried, too many settings! 🤪 I'm going to get the chainsaw and wood splitter out to reset my spirit 😲😲😂😂
 
I think changing from US2 to USE fixed the problem of not charging. We'll see if it wakes itself up in the morning. My head is fried, too many settings! 🤪 I'm going to get the chainsaw and wood splitter out to reset my spirit 😲😲😂😂
You know, ALL this solar sh-t has too many settings that are not clear on how they interact. This should really boil down much more simply than it seems to.
 
I think changing from US2 to USE fixed the problem of not charging. We'll see if it wakes itself up in the morning. My head is fried, too many settings! 🤪 I'm going to get the chainsaw and wood splitter out to reset my spirit 😲😲😂😂
Don't forget the issue with no re-bulk charging on next day if the battery voltage is not less than 2V lower than float voltage in USE mode
Due to LFP unique flat voltage curve, you will have issue of not triggering any re-rebulk charging if you set float voltage too low.
 

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