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Renogy Rover Lithium settings

solarstuff

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Hey folks, are Renogy's default Li settings anything I need to worry about? My battery suddenly undervolts quite a lot during routine loads when the sun goes down.
 

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The Li settings seem semi reasonable. Are you sure your batteries are getting fully charged during the day? Voltage?
What are your "routine loads"?
It not loads or charge (but I'll investigate). It seems to happen in a minute, regardless of load or sun, and drains it from 60-70 percent to below 15.
With no head on wires or lugs either.
 
What batteries? If your battery(s) drain 70% in a minute without a load, your battery is toast.
That's the fear in th back of my brain...but they are brand new Renogy 170ah smart lithium's. Approx a month old.

But it's intermittent. Other times it works as advertised, maintains loads, drops approximately....and then this happens again.
 
That's the fear in th back of my brain...but they are brand new Renogy 170ah smart lithium's. Approx a month old.

But it's intermittent. Other times it works as advertised, maintains loads, drops approximately....and then this happens again.
Do you have a volt meter to test the individual battery voltages?
Have they been severely over discharged or anything unusual happen to them?
Have you checked that the connections are tight?
How are you charging these batteries and what kinds of volts to they get to when you think they are charged?
 
What batteries? If your battery(s) drain 70% in a minute without a load, your battery is toast.
2x Renovgy smart lithium 170ah
Do you have a volt meter to test the individual battery voltages?
Meter reads 12.7v and 83% on both 170ah batts right now-- wired together for 340ah.
Have they been severely over discharged or anything unusual happen to them?
Not that I know of.
Have you checked that the connections are tight?
Yes, and no heat building anywhere (brought a problem with the fuse to the group last month that was resolved with the group's help)
How are you charging these batteries and what kinds of volts to they get to when you think they are charged?
Charging from 300w solar via renogy rover li 30a MPPT.
 
Meter reads 12.7v and 83%
12.7V should read more like 10-20%.

I am wondering if you have not cycled your batteries to full charge and it thinks "full" is much lower than it should be. What voltage do you see on the batteries, with a meter, when you are at your maximum charge? Does it actually stop charging because it thinks its full?
 
12.7V should read more like 10-20%.

I am wondering if you have not cycled your batteries to full charge and it thinks "full" is much lower than it should be. What voltage do you see on the batteries, with a meter, when you are at your maximum charge? Does it actually stop charging because it thinks its full?
Maybe... Here's the chart I was going off of. Batteries according to multi with solar disco'd and inverter off is 12.7v now but MPPT reads 79%?
 

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With you lithium charge profile it should charge up to at least 13.8V for your batteries to be fully charged.
How high voltage have you been seeing on your meter for charging?
 
It seems you haven't really fully charged your battery bank, as Mr S. has suggested.
With only 300W of solar it's going to take several days to charge up 340Ah of battery bank.
340Ah x 12.8V = 4,352Wh of stored capacity. 4,352Wh / 300W = 14.5h.
Even with 5 hours of sun a day that's three days to charge from empty (with no loads on them).
Do you have a grid/mains charger you can use to fully charge the batteries?

I also have the Renogy Rover 30A Li. A couple of points of note once you get your bank fully charged up:
  • The built-in state of charge monitor uses voltage only and is calibrated for lead acid so it's not accurate for your use case. You're better off getting a shunt-based battery monitor. Search the forums for options.

  • The built-in lithium settings are OK, but problematic in one important sense. My observation is that the float listing of ----- doesn't mean that it doesn't apply a float voltage after reaching the boost voltage setting of 14.4V. For my Renogy SCCs it means that it never drops the voltage at all, so it stays at 14.4V as long as you're getting sun and there aren't loads on the system.

    I prefer the User settings where I can apply more control. For example in my 180Ah LFP bank, I drop the High volt disconnect down to 14.4V, Boost voltage to 14.0V, Boost Charge Time to 10 mins. Float to 13.5V. Equalize charge voltage to 14.0V and Equalize charge time to 0 since that's only for flooded lead acids. Etc.
 
Going through the renogy settings and I could use a heads-up what these two settings refer to.

Also, where did you set Equalization to 0 time at?

Thanks for your help, all.

-Is the pic with a 50% battery icon the undervoltage?

-Is the pic with an empty battery icon the low voltage disconnect?
 

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-Is the pic with a 50% battery icon the undervoltage?
The battery with 11.1V is almost stone cold empty! Depending on how low an individual cells is, it any are below 2.5V they are being damaged. Do you have an app or some way to show individual cell voltage inside the battery.

You seriously NEED to work on getting these charged before pulling them down further.
 
The battery with 11.1V is almost stone cold empty! Depending on how low an individual cells is, it any are below 2.5V they are being damaged. Do you have an app or some way to show individual cell voltage inside the battery.

You seriously NEED to work on getting these charged before pulling them down further.
Thanks Mr. S & all. i will let the batteries charge and try to get a few more panels or before more use.

Changed mppt settings under USR.

Do these work better? Cobbling together knowledge here :)

Equalization 14v
Boost 14v
Float 13.6v

Half-emoty battery icon (undervoltage?) 13.2v
Low voltage disconnect 12.3v
 
The battery with 11.1V is almost stone cold empty! Depending on how low an individual cells is, it any are below 2.5V they are being damaged. Do you have an app or some way to show individual cell voltage inside the battery.

You seriously NEED to work on getting these charged before pulling them down further.
No that was one of the renogy settings. I posted to confirm if I'm right that the half battery icon (in USR settings) was undervoltage and the empty battery was low voltage disconnect.

After a day of little sun but no load both batteries read 12.8.
 
It seems you haven't really fully charged your battery bank, as Mr S. has suggested.
With only 300W of solar it's going to take several days to charge up 340Ah of battery bank.
340Ah x 12.8V = 4,352Wh of stored capacity. 4,352Wh / 300W = 14.5h.
Even with 5 hours of sun a day that's three days to charge from empty (with no loads on them).
Do you have a grid/mains charger you can use to fully charge the batteries?

I also have the Renogy Rover 30A Li. A couple of points of note once you get your bank fully charged up:
  • The built-in state of charge monitor uses voltage only and is calibrated for lead acid so it's not accurate for your use case. You're better off getting a shunt-based battery monitor. Search the forums for options.

  • The built-in lithium settings are OK, but problematic in one important sense. My observation is that the float listing of ----- doesn't mean that it doesn't apply a float voltage after reaching the boost voltage setting of 14.4V. For my Renogy SCCs it means that it never drops the voltage at all, so it stays at 14.4V as long as you're getting sun and there aren't loads on the system.

    I prefer the User settings where I can apply more control. For example in my 180Ah LFP bank, I drop the High volt disconnect down to 14.4V, Boost voltage to 14.0V, Boost Charge Time to 10 mins. Float to 13.5V. Equalize charge voltage to 14.0V and Equalize charge time to 0 since that's only for flooded lead acids. Etc.
Could really use your advice on the equalization settings. Are my assumptions and settings right?

Equalization 14v
Boost 14v
Float 13.6v

Half-empty batt=undervoltage: 13.2v
Empty batt=low voltage disconnect 12.3v

I will keep load off and add panels when I can but any advice appreciated.
 
Equalization 14v
You should have equalization time set to zero so this would not matter. (zero means in never equalizes, that is a lead acid battery concept).
Boost 14v
Float 13.6v
Looks good. If you store your system, i would float lower than 13.6V as they like to rest lower. If using everyday, these are great numbers.
Half-empty batt=undervoltage: 13.2v
Empty batt=low voltage disconnect 12.3v
It sounds like these are just display options. According to the chart i sent, about 13.15V would be 50% but its for your visual use so whatever number makes sense to you.
 
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