Epever charge controller.

[Loveshack]

I really appreciate your time. This has really been bothering me.
I have 6 230amp/hr FLA batteries connected in series and parallel. Giving me 690 12 v amp/hrs

i have 4 x 100watt panels. They are paired up, connected in parallel. Each pair of two goes to a separate mppt. Each mppt are connected to the battery bank. The most I have seen is about 9amps from each pair.

As as well as solar we have a generator and an alternator. We are on a boat and are trying to have solar meet our needs. If. It we can supliment our power with the other methods. So far at night our batteries have been 12.6 or better.

12.5 has been our lowest voltage yet before recharging.

[sensij]

Look closely at the numbers. It shows the PV system is operating at 38.96 W, producing 2.43 A at 15.99 V. The charge controller is boosting the current to 2.97 A, and the battery voltage is 13.12 V... suggesting something close to 100% conversion. The controller is doing what it is supposed to do.

The first stage of the charge cycle is the bulk stage, in which the controller is pushing all of the available current to the battery. The voltage you measure during this charge stage will be OCV + (I * Ri), where OCV = the open circuit voltage of the battery, and Ri is the internal resistance of the battery. Let's say your internal resistance was 0.1 Ohm. That means that under the conditions you are observing, the OCV = 13.12 - (0.1 * 2.97) = 12.8 V.

As you put more charge into the battery, the open circuit battery voltage will climb. Once the measured voltage reaches your setpoint of 14.8 V, the controller will hold at that voltage. This is the second stage of charging, known as absorb (or boost, in some sections of their manual). Current will gradually taper off as OCV continues to rise. Taken to the extreme, current would eventually fall to a very low value necessary to match the self-discharge of the battery, and the measured voltage would be the same as the OCV.

Instead of taking it all the way to current equals zero, it drops the voltage setpoint from the boost value to the float value. For this controller, that occurs after 2 hours by default, although it is user settable from 10 min to 180 min. Better controllers don't use a timer, but actually watch for the charge current to fall to a specified rate, say 3-5% of the battery capacity in Ah.

If you are never seeing it hit the voltage you specify, that means you are not supplying enough energy to get the battery out of bulk and into absorb. If you chronically operate this way, the battery isn't going to last very long. So... more information is needed to take this further:

What is the battery capacity in Ah?
How much solar do you have (looks like it might be a 50 W panel?)
How much energy are you trying to consume each day form the battery?
How low does the voltage get before you recharge?

If your battery is FLA, you should use specific gravity to fine tune your charging plan, but it sounds like you've got a bigger mismatch problem that even SOC based on voltage is revealing.

[Loveshack]

IMG_7295.JPG This a picture of the app. It says it's in boost mode yet the charge value is 13.12 and not 14.8 (boost parameter I have set)

[Loveshack]

I think part of my confusion is because I am using a ebox-wifi-01 to monitor my panels. Using this app it tells me "boost" or "equalizing " with an icon above, yet my numbers while the icon is displayed do not match my parameters I have set . Should I just ignor the icons.
Also I have my boost set to 14.8. I have also never seen this value produced.
Is there a parameter setting that you could recommend as a test to make sure that I am setting the mppt advanced parameter settings correctly.
I have replaced my batteries this year and I am trying to follow the manufacturers recommendations exactly to help prolong the batteries life.
Thanks.

[sensij]

Thank you for your quick and accurate response. Am I able to force an equalization or pick a different date for equalizing? The reason for this would be to disconnect some of my 12v equipment during the equalization

You might be able to trick it into EQ by setting the date to Aug 28. You would just need to leave it that way until the 28th actually passes, if you don't want it to EQ again.

[Loveshack]

Thank you for your quick and accurate response. Am I able to force an equalization or pick a different date for equalizing? The reason for this would be to disconnect some of my 12v equipment during the equalization

[sensij]

Welcome to the forum!


From the manual:

The controller will equalize the battery on 28th each month. The constant equalization period is 0~180 minutes. If the equalization isn't accomplished in
one-time, the equalization recharge time will be accumulated until the set time is finished. Equalize charge and boost charge are not carried out constantly in a full charge process to avoid too much gas precipitation or overheating of battery.

[Loveshack]

Hi I am new to this forum. I was wondering if anyone had any experience with an epever tracer a series mppt. Specifically with the advanced battery charge settings. I have changed the parameters for equalization to 15.60, but I never see the mppt actually charge at this level. Any help would be appreciated.