Epever tracer issue?

[Palongee1]

Hi, newbie here. I have a EPEVER 3210 that I am having an issue with. I have two 275 W panels connected in series. The system seems to work as it should most of the time. On occasion in full sun the charge controller shows a lower voltage ie 26.4 v about half of what it typically does in full sun. If I unplug everything and plug the panels back in it will return to the higher voltage around 60v and begin working normally again. I am including some pictures, the lower voltage picture and the higher voltage picture. Any idea on what might be causing this? Thank you, Mike.

[Palongee1]

Apparently my pics didn’t upload. I gotta figure that out.

[SunEagle]

Hello Palongee1 and welcome to Solar Panel Talk

Not being able to up load pictures may be due to their pixel size or because you are new to the forum the software may not allow you to upload to keep someone from creating spam.

I am unfamiliar with that CC but my first question is what is the SOC of your battery system. Sometimes a CC will reduce the charging amps going to the battery because it is full but I am not sure about why you are seeing a lower voltage.

[Palongee1]

Thanks for the reply. The battery was still well below float charge. Im using nissan leaf modules for the battery bank. I talked to the folks at battleborn batteries and was told that they see alot of issues with these charge controllers not playing well with lithium batteries. Searching online I don't find any other mention of that. When this does happen its acting like only one panel is providing power. I believe its an issue with the charge controller. Very new to this stuff. Originally the setup only had one panel, now it has two. Thanks for your help IMG_0246.jpgIMG_6324.JPG

[SunEagle]

Thanks for the reply. The battery was still well below float charge. Im using nissan leaf modules for the battery bank. I talked to the folks at battleborn batteries and was told that they see alot of issues with these charge controllers not playing well with lithium batteries. Searching online I don't find any other mention of that. When this does happen its acting like only one panel is providing power. I believe its an issue with the charge controller. Very new to this stuff. Originally the setup only had one panel, now it has two. Thanks for your help IMG_0246.jpgIMG_6324.JPG

Well I know that most solar CC's are not enough for Lithium batteries. You need some type of BMS (battery management system) to regulate the proper charge to each cell.

My guess is that CC does not like the Li battery system and lowering the voltage so it doesn't fry anything.

[Palongee1]

I have a bms, all cells are within 10-12mv so pretty well balanced.

[bcroe]

I have a comment. In one picture the panels are above the wall, but in another
they are dropped down and shadowed. You would do better keeping them in
a position of no shadow, even it is a poorer calculated elevation angle. Bruce Roe

[Palongee1]

Thank you Bruce! I agree. The picture where it is shaded is late day, when I added a second panel to the frame I had to change the orientation of the panels. The other picture is with a single panel. I can change the angle a bit more to get maybe another 30 minutes of setting sun. In the shortest days of winter it gets good sun from 9am until about 3pm with sun setting at 5. Keep in mind there are two 275 watt panels and my battery is only about 2200 watts and consuming about 500 watts over 24 hr period. If the sun comes up as it has been lately, that battery is topped off before noon then floating the rest of the day. The setup runs a automatic gate which has 2 small 12 volt batteries in series that I have configured to keep charged up in case the main battery gets to disconnect voltage. The system also runs a modem, router, point to point internet radio and a internet access point. All together just under 1a constant draw or around 20 watts per hour. As I said, I’m pretty new to the solar stuff and very intrigued. It’s been running almost a year now. By my math I only have about 4 days that it would continue with zero charge coming in. I added the second panel to attempt to scavenge even the weakest sun on those cloudy days. We get a lot of sunny days in southern Idaho. The issue is, when the charge controller is putting out the lower voltage I’m only getting about half the watts To the battery that I should be which kinda defeats the purpose of the second panel when that happens. It’s odd because it works normal one day, then the next day it does this. I have a email off to epever, we’ll see what they have to say. Thank you again! Any other input would be great!

[SunEagle]

Now I am a little confused and trying to get an idea of exactly what your system is so please clarify what I state below as truth or guess.

The original system only had one 275w panel but you had a 24v battery system which is confusing because unless that panel could provide about 36volts it was not enough to keep the batteries charged.

Now you added a second 275w panel but the CC lowers the voltage by half sometimes, which may be due to either wiring, a bad CC or shade.

You also state that the battery is only 2200 watts and the "system" consumes 500watts over a 24 hr period. So I am guessing you really mean the battery is rated 2200watt hours and you consume 500 watt hours in a day.

So my question is did you follow some directions about how to add a second 275w panel that your gate opener would be happy with or did you just add the second panel without knowing the system requirements?

[Palongee1]

Sorry if I wasn’t clear. The panel puts out more than 24v. Rated voltage is 31v, open circuit voltage is 39. The single panel charged fine until winter came and I decided to add another panel. As far as wiring goes, I have a boost/buck running from the cc load to the batteries for the gate operator that keep those batteries topped off, im
not running the panels directly to the gate operator. The operator is 24v and runs off its own batteries when it cycles. Yes, by my testing the battery bank has about 2200wh capacity and consumes about 500wh a day.

[SunEagle]

Sorry if I wasn’t clear. The panel puts out more than 24v. Rated voltage is 31v, open circuit voltage is 39. The single panel charged fine until winter came and I decided to add another panel. As far as wiring goes, I have a boost/buck running from the cc load to the batteries for the gate operator that keep those batteries topped off, im
not running the panels directly to the gate operator. The operator is 24v and runs off its own batteries when it cycles. Yes, by my testing the battery bank has about 2200wh capacity and consumes about 500wh a day.

Thanks I understand your system better. Although based on other information a 31V panel output is barely enough to keep a 24V battery happy. But if that is what the system works with then ok.

I still think the CC is lowering it's output voltage due to some programing issue. It might not like the 60v input and sometimes reacts by cutting it in half. Again the output charging amps is in relation to the SOC of the battery system. The higher the SOC the less charging amps it is subjected to. At least that is how a FLA system works. I am unsure how your BMS and Li batteries work with that CC.

[Palongee1]

Thanks. The single panel was charging at around 9a @ 26-30v and keeping the battery charged nicely. The charge controller claims a max open circuit voltage of 100v. I understand the charging amps are reduced as the SOC of the battery increases. IMG_0610.jpg I will keep an eye on it. Nothing back from epever yet.

[Ho jo]

I used a epever 3210an controller for about a year.
I was using lead acid.
With the same issues you're having.
A passing cloud will cause the charge controller to get lost tracking.
And the array voltage will drop and get stuck.
Having to constantly watch then unplug and reconnect to get it going again.
Imo A better controller would be more reliable.