Solar and lithium

steveswift

steveswift

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swift edge 494
Hi guys , please see attached info , (which I don’t quite understand) does my Solar appear to be working to full capacity ?
There’s 600w up there , and 220ah of lithium in batteries

I’ve been parked up for a week without charging… general power use , tv and lights , light use of microwave and kettle via inverter

Cheers

E3299B6D-2041-445D-BF09-B0885F9CACED.png 1606FDBF-6C9B-4A6D-A179-D536D047F2C3.png 69DA8969-D38B-4E2B-8DF2-16699F7EE467.png
 
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That the solar keeps reaching an absorption phase suggests the batteries are approaching full charge. Once at absorption, and later float the wattage from the panels will reduce. The shunt however thinks differently if that suggests only 67% full. Do you have any BMS on your batteries that allows you to check what the batteries are actually at?

You may need to look at the configuration of the smartshunt. Quite possibly there has been some drift and you need to look specifically at things like the full charge voltages (always a challenge to get these right for your specific batteries, and there are other threads about with differing suggestions). Look in that settings cog on the top right where there is a red exclamation mark. That exclamation suggests there is some attention needed, perhaps an update to firmware.
 
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Of course it all depends on the weather or more specifically the sun but I would expect higher Pmax if you were parked anywhere near us (Shropshire) as a comparison and only 540 watts on the roof.

IMG_1546.png
 
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Kannon Fodda said:
That the solar keeps reaching an absorption phase suggests the batteries are approaching full charge. Once at absorption, and later float the wattage from the panels will reduce. The shunt however thinks differently if that suggests only 67% full. Do you have any BMS on your batteries that allows you to check what the batteries are actually at?

You may need to look at the configuration of the smartshunt. Quite possibly there has been some drift and you need to look specifically at things like the full charge voltages (always a challenge to get these right for your specific batteries, and there are other threads about with differing suggestions). Look in that settings cog on the top right where there is a red exclamation mark. That exclamation suggests there is some attention needed, perhaps an update to firmware.
Click to expand...
Hi many thanks , indeed the exclamation mark indicated firmware update was needed , it’s now showing batteries are 100% charged ?

No bms to my knowledge

Many thanks
 
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funflair said:
Of course it all depends on the weather or more specifically the sun but I would expect higher Pmax if you were parked anywhere near us (Shropshire) as a comparison and only 540 watts on the roof.

View attachment 738568
Click to expand...
Hi there. The figures lose me 😳 that said I am half in the shade

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Kannon Fodda said:
That the solar keeps reaching an absorption phase suggests the batteries are approaching full charge. Once at absorption, and later float the wattage from the panels will reduce. The shunt however thinks differently if that suggests only 67% full. Do you have any BMS on your batteries that allows you to check what the batteries are actually at?

You may need to look at the configuration of the smartshunt. Quite possibly there has been some drift and you need to look specifically at things like the full charge voltages (always a challenge to get these right for your specific batteries, and there are other threads about with differing suggestions). Look in that settings cog on the top right where there is a red exclamation mark. That exclamation suggests there is some attention needed, perhaps an update to firmware.
Click to expand...
Sorry , do you see a BMS? Do forgive me I don’t understand any of this , all I know is it appears to give me the power I need , see attached

59EE3408-C494-4D0E-ABF1-E9CA055CA7A4.jpeg
 
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Open your solar app > click the cog symbol top right > click 'battery' and take a screenshot of those settings to post here.
 
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steveswift said:
Hi there. The figures lose me 😳 that said I am half in the shade
Click to expand...
OK half in the shade is not good ;) and might explain some things but basically Pmax is the Peak watts the system has produced, you have 600 watts on the roof so on a good day ou should see Pmax at 600 watts or even more sometimes. I am guessing that you possibly have two panels in series as the panel voltage is showing at 38.71v in your first photo, this could be making any shading effect even worse.
 
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BMS - Battery Management System - is usually integrated within the lithium battery casing. It's electronics that amongst other things monitor each of the battery cells to keep them balanced. Some BMS systems can be remotely monitored, usually by a bluetooth smart phone app. You would have been told about it's existence, if available, by the battery supplier / installer.

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steveswift said:
Hi many thanks , indeed the exclamation mark indicated firmware update was needed , it’s now showing batteries are 100% charged ?

No bms to my knowledge

Many thanks
Click to expand...
Oh I have this , kindly see attached , cheers

CFCE7E58-7A11-4410-8774-E11110063929.jpeg
 
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Ditcha said:
Looking at your pics your smartshunt has a firmware update notification.
Click to expand...
Yes thank you , someone else pointed that out and I’ve since updated it , thanks

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I can spot a problem, forget the bms, it’s built in the battery and probably no Bluetooth comms, not a problem.
Show us you battery cable from solar charger to the battery. And tell us what size it is. Your settings in the solar charger are ok. Something else it’s stopping you to fully charge.
 
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Raul said:
I can spot a problem, forget the bms, it’s built in the battery and probably no Bluetooth comms, not a problem.
Show us you battery cable from solar charger to the battery. And tell us what size it is. Your settings in the solar charger are ok. Something else it’s stopping you to fully charge.
Click to expand...
The OP has said that the battery is showing 100% now following the shunt firmware update, is it worth him posting the battery settings page from the shunt to see what the battery SOC is set to?
 
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He is only going to experience this again. Have you spotted the problem? It’s displayed in the photos attached.
 
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Raul said:
He is only going to experience this again. Have you spotted the problem? It’s displayed in the photos attached.
Click to expand...
Are you going to say tat there is something on the battery -ve post that should be after the shunt ? or is that temperature sensing ? which should be on the +ve.

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funflair said:
Are you going to say tat there is something on the battery -ve post that should be after the shunt ? or is that temperature sensing ? which should be on the +ve.
Click to expand...
That temp sensor is coming from his multiplus and should be connected to the negative side, when his app was updated he must have the shunt setting to reset state of charge to 100% on reset that's how it's now showing 100% after update.
 
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steveswift said:
Yes thank you , someone else pointed that out and I’ve since updated it , thanks
Click to expand...
Looking at your last 2 days of solar the voltage is showing 14.2 max which is your set absorption voltage so your batteries are full, if you get to float voltage today reset the shunt to 100% and see how it goes it seems as if you have a bit drift caused by your shunt settings so might need to tweak them, I would also set battery soc on reset to keep soc and take it from there.
 
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funflair said:
Are you going to say tat there is something on the battery -ve post that should be after the shunt ? or is that temperature sensing ? which should be on the +ve.
Click to expand...
No nothing in that area.
If you look at the solar charger it has 14.08v and the shunt at the battery end is reading 13.36v ish.
Either a cable resistance connection, or very undersized cables. As far as the solar charger is concerned it’s delivering, but the same value it’s not reached by the battery terminal. Fit a voltage sense to compensate for the voltage drop, or upgrade the cables. OP has not given any feedback on this area yet.
The only time voltage will rise is close to full battery, low or nil loads and low power harvest. All of this when enters float on CV.
 
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I have just realised the op doesn't have a ve smart network set up with his shunt and mppt and multiplus ( if he has a smart dongle) this would help to compensate for any voltage drops in the system.
 
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Hi thanks for all this , however , way beyond me ! So after reset I’m now getting a false reading of battery state of charge , is that right ?

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Raul said:
I can spot a problem, forget the bms, it’s built in the battery and probably no Bluetooth comms, not a problem.
Show us you battery cable from solar charger to the battery. And tell us what size it is. Your settings in the solar charger are ok. Something else it’s stopping you to fully charge.
Click to expand...
Ok when back in van I’ll do that , they are all very chunky cables though
 
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steveswift said:
Ok when back in van I’ll do that , they are all very chunky cables though
Click to expand...

If they are then you’ve probably got a high resistance connection because something is dropping the voltage.

If you can measure with a DVM between the solar controller output and the battery post and detect approximately 0.7V then that’s confirmation that you have a high resistance in your charge path.

You need to measure between the two positive connections and also between the two negative connections. The resistance (volt drop) could be in either, or both, of the charge leads.

Ian
 
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In the OP's photos, why is the solar voltage 38.7 volts? Isn't that too high? Are two panels connected in series rather than parallel?
 
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G7UXG said:
In the OP's photos, why is the solar voltage 38.7 volts? Isn't that too high? Are two panels connected in series rather than parallel?
Click to expand...
He has 600w would imagine 2 parallel 2 series so 4 150w panels just a guess.
 
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