trying to understand what my Classic 150 is telling me

[Skip]

I've been through the manual many times, but am not sure I'm interpreting the Classic 150 status output correctly.
I have six 420W Q panels. Three series pair. Total rated output should be around 2500 watts at 48 volts DC going to the Classic.
My battery bank and inverter are 24 volt.

Today, sunny skies with some thin whispy clouds. Sun bright enough you can't look at it. High noon.

Classic 150 main status screen reads: IN 92.2V, Watts 400 (more or less) KWh 2.4 BATT 28.4V, 13A (more or less), Absorb.

What does the 400 Watts mean? Surely that's not all I'm getting from my panels? What tells me the truth about how many charging watts are being supplied to the battery bank?
For this lead acid bank I need the full 2500 output for the batteries to get a full charge.

My Q panels data sheet states minimum watts of 314.4 (each) at the MPP at normal operating conditions. What are normal operating conditions?
Current temperature is 48 degrees F.
Panels have been in service for about 18 months
Panels are oriented perpendicular to the angle of the sun at local noon and fall & spring equinox.
Based on the performance at low irradiance chart, I should have at least 95% efficiency.

 

[MisterSandals]

Three series pair. Total rated output should be around 2500 watts at 48 volts DC going to the Classic.

What is "three series pair"?

Classic 150 main status screen reads: IN 92.2V, Watts 400 (more or less)

Sounds like 2P3S array (2x Vmp, 3x Imp)

What does the 400 Watts mean?

it means that with your battery at 28.4V, you battery is nearly full and your charge controller has tapered charging as it ends the absorb charge cycle.

What are your Classic 150 charge parameters? Can you post a pic?

 

[OzSolar]

Absorb

The Midnite thinks that your batteries are nearly full and limiting the wattage (current) going to the batteries.

Below is a generic chart that hopefully will clear things up.

NOC is the best your panels will do in real world conditions.

 

[Skip]

What is "three series pair"?


Sounds like 2P3S array (2x Vmp, 3x Imp)

it means that with your battery at 28.4V, you battery is nearly full and your charge controller has tapered charging as it ends the absorb charge cycle.

What are your Classic 150 charge parameters? Can you post a pic?

Each pair of panels is in a series. the three pairs wired in parallel to the combiner box - that's what I was trying to say in poor shorthand.
The reason I'm asking is that I'm in the process of replacing my AGM batteries with LifePo. The AGM do not hold a charge. At dusk, they will drop to 26 v and within an hour after that to around 25 and by morning they'll be at 24.6 or less with a 1 to 2 amp load during the night. Manufacturer keeps blaming me for not fully charging them and will not honor the warranty. I don't know how to prove to them that they are getting fully charged on sunny days, but are not capable of holding that with very minimal loads.
Also, I want to make sure my LifePo's will get a full charge via solar.
I've already established that my generator/inverter combo is up to the task.

This is what I had believed early on - that the solar array/Classic 150 setup is very efficient and bring the batteries up to full charge early in the day.
I'll watch the status screen more closely in the morning.

Classic settings are:
Charging is 28.2 v; Float is 27.2v; Absorb time is 3:47. Kilovault recommends against using equalize.
Ending Amps 0.3; ReBulk 24.4v
Under Limits, max charge is set to 28.4v

What is "2P3S array (2x Vmp, 3x Imp)" ?

I'm pretty smart in my fields of expertise. This area is NOT one of those. I've been steadily climbing the steep learning curve, but have a LONG way to go.

Thanks

 

[Skip]

The Midnite thinks that your batteries are nearly full and limiting the wattage (current) going to the batteries.

Below is a generic chart that hopefully will clear things up.

NOC is the best your panels will do in real world conditions.

This is helpful.

So, would a sunny winter day in the Northern plains with temps in the high 40's be considered "normal"?

 

[Skip]

Each pair of panels is in a series. the three pairs wired in parallel to the combiner box - that's what I was trying to say in poor shorthand.
The reason I'm asking is that I'm in the process of replacing my AGM batteries with LifePo. The AGM do not hold a charge. At dusk, they will drop to 26 v and within an hour after that to around 25 and by morning they'll be at 24.6 or less with a 1 to 2 amp load during the night. Manufacturer keeps blaming me for not fully charging them and will not honor the warranty. I don't know how to prove to them that they are getting fully charged on sunny days, but are not capable of holding that with very minimal loads.
Also, I want to make sure my LifePo's will get a full charge via solar.
I've already established that my generator/inverter combo is up to the task.

This is what I had believed early on - that the solar array/Classic 150 setup is very efficient and bring the batteries up to full charge early in the day.
I'll watch the status screen more closely in the morning.

Classic settings are:
Charging is 28.2 v; Float is 27.2v; Absorb time is 3:47. Kilovault recommends against using equalize.
Ending Amps 0.3; ReBulk 24.4v
Under Limits, max charge is set to 28.4v

What is "2P3S array (2x Vmp, 3x Imp)" ?

I'm pretty smart in my fields of expertise. This area is NOT one of those. I've been steadily climbing the steep learning curve, but have a LONG way to go.

Thanks

Meant to state that Absorb charging is 28.2v

 

[OzSolar]

Meant to state that Absorb charging is 28.2v

Whoa.... lead acid or lithium?

So, would a sunny winter day in the Northern plains with temps in the high 40's be considered "normal"?

Yes, IMHO, Anything outside of the lab is "normal". Every so often you'll get to have some fun watching your array hit STC during cloud edge events.

 

[MisterSandals]

Hmm, i was writing up a question asking about whether you equalized lately but saw that Kilovolt recommends against using equalize. This is baffling to me but their recommendations trump mine.

But before discarding them, i'd certainly consider a good equalization (desulfation) charge.

Do AGM Batteries Need To Be Equalized?

Equalization of lead-acid batteries falls in the regular maintenance program. It is an important step to be followed to prevent the battery from being deeply di

batteryhint.com

What is "2P3S array (2x Vmp, 3x Imp)" ?

I meant to write "2S3P" which is shorthand for your shorthand:
2 panels in series, 3 of those in parallel.
This results in an array 2x a single panel Vmp and 3x a single panel Imp.

I've been steadily climbing the steep learning curve, but have a LONG way to go.

Looks like you're doing great!

 

[Skip]

Whoa.... lead acid or lithium?


Yes, IMHO, Anything outside of the lab is "normal". Every so often you'll get to have some fun watching your array hit STC during cloud edge events.

Current setup is lead acid AGM. I'm about to install LifePo - of course, settings will have to change.

 

[Skip]

Hmm, i was writing up a question asking about whether you equalized lately but saw that Kilovolt recommends against using equalize. This is baffling to me but their recommendations trump mine.

But before discarding them, i'd certainly consider a good equalization (desulfation) charge.

Do AGM Batteries Need To Be Equalized?

Equalization of lead-acid batteries falls in the regular maintenance program. It is an important step to be followed to prevent the battery from being deeply di

batteryhint.com

I meant to write "2S3P" which is shorthand for your shorthand:
2 panels in series, 3 of those in parallel.
This results in an array 2x a single panel Vmp and 3x a single panel Imp.


Looks like you're doing great!

What I keep coming back to is that I believe the Kilovault batteries were damaged. The system went live the end of June 2021. Everything was great - then short, cloudy winter days came along and I needed to start using the generator to supplement. I carefully checked all the settings based on the documentation I had. Right off the back, the Conext SW started pumping 29 volts into the batteries. Called Alt-E store. They didn't think that was good. Went over all the settings. The brought in a Kilovault tech support. He couldn't figure it out. I needed power - couldn't shut everything down. Finally contacted Schneider Electric. First tech was baffled. Second tech finally sent me the magic "Conext Kilovault Integration Guide" This manual has the magic temperature compensation value. That fixed the problem. All this took almost three weeks. I could go weeks with no power. I suspect a series of 2 hour charging sessions at 29 volts damaged the batteries. Kilovault won't address this issue or acknowledge the problem. When I bought the batteries, they had been on the market only 6 months. The integration guide wasn't made available to me. Woops. I dealt with this lack of capacity all last winter. Finally have had enough. Started getting smart and now I know this is not normal. (The low capacity, not getting smart.)

Lessons learned: Don't start a new system with expensive batteries.

 

[OzSolar]

Lessons learned: Don't start a new system with expensive batteries.

Yep. I used to tell all of my off grid customers the same thing when I refused to install anything other than a minimal set of off brand T105's. "you aren't ready for good batteries until you prove you can take care of a battery". Thankfully (or not) that was a lesson I learned at the expense of many others when I got called in to clean up messes left behind by the latest "best" off grid solar installer of the week.

 

[Skip]

Yep. I used to tell all of my off grid customers the same thing when I refused to install anything other than a minimal set of off brand T105's. "you aren't ready for good batteries until you prove you can take care of a battery". Thankfully (or not) that was a lesson I learned at the expense of many others when I got called in to clean up messes left behind by the latest "best" off grid solar installer of the week.

I'm in central Montana up against the east side of the Rockies. Very rural. I've been trying to find a solar expert I can pay just to come out and advise me, but no one wants to be bothered with that. Everything in Montana is at least a full day's drive away.
There's no such thing as a free education.

 

[Skip]

I'm in central Montana up against the east side of the Rockies. Very rural. I've been trying to find a solar expert I can pay just to come out and advise me, but no one wants to be bothered with that. Everything in Montana is at least a full day's drive away.
There's no such thing as a free education.

Yep. I used to tell all of my off grid customers the same thing when I refused to install anything other than a minimal set of off brand T105's. "you aren't ready for good batteries until you prove you can take care of a battery". Thankfully (or not) that was a lesson I learned at the expense of many others when I got called in to clean up messes left behind by the latest "best" off grid solar installer of the week.

I'm grateful for the expert guidance on this forum, or I'd be calling the power company to hook me up about now.