question

nicomauritius avatar image

Could wrong voltage from MPPT 100/50 damage super pack battery?

Good day to you all,

I have installed the following:

Solar array : 800W (Voc 43V)

1x MPPT charger is 100/50

1x Battery: Super pack 25.6V


The system worked well until, the battery was fully discharged and low voltage protection activated.

Than the MPPT couldn't start recharging the battery again. Voltage at the battery was 14.7 V with solar panel input (in float mode), and 0V without.

I discovered later that MPPT voltage auto detect was the issue, and changed the settings manually to 24V using the app. It looks like its working. I am waiting for another blackout to see it MPPT remember that setting.

My question:

Could the prolonged application of 14V (see in red below) from the MPPT on the battery had done some damages to it? Knowing the battery is not supposed to go below 20V.


Thank you for your inputs

Cheers

Nico

Days ago Date Yield(Wh) Max. PV power(W) Max. PV voltage(V) Min. battery voltage(V) Max. battery voltage(V) Time in bulk(m) Time in absorption(m) Time in float(m) Last error 2nd last error 3rd last error 4th last error
0 12/9/2020 0 220 42.07 0 23.8 3 5 225 34 0 0 0
1 12/8/2020 0 1 42.89 0 14.78 0 3 518 34 0 0 0
2 12/7/2020 0 2 43.65 0 15.1 0 3 260 34 0 0 0
3 12/6/2020 0 2 43.65 0 14.91 3 1 341 0 0 0 0
4 12/5/2020 20 3 43.91 0 14.78 0 2 802 0 0 0 0
5 12/4/2020 1120 615 43.65 0 28.66 419 90 290 34 0 0 0
6 12/3/2020 1870 811 42.86 25.38 28.7 416 64 314 34 0 0 0
7 12/2/2020 490 568 43.65 0 26.25 228 4 198 34 2 34 0
8 12/1/2020 0 2 43.09 0 14.84 1 3 494 34 0 0 0
9 11/30/2020 0 1 44.44 0 17.14 1 1 616 0 0 0 0
10 11/29/2020 2100 803 40.75 0 27.35 808 0 0 0 0 0 0
11 11/28/2020 2480 845 41.68 24.23 28.52 781 7 17 0 0 0 0
12 11/27/2020 2000 800 43.55 24.5 28.67 540 9 265 0 0 0 0
13 11/26/2020 2820 693 41.42 24.45 28.5 760 50 0 0 0 0 0
14 11/25/2020 2360 770 43.55 24.48 28.74 494 90 220 0 0 0 0
15 11/24/2020 2460 843 42.42 24.58 28.5 535 18 251 0 0 0 0
16 11/23/2020 2270 881 43.26 24.52 28.63 588 80 132 0 0 0 0
battery system voltage
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2 Answers
klim8skeptic avatar image
klim8skeptic answered ·

Error code 34 looks bad. Check your array wiring, making sure that the mppt is wired correctly. (no wiring bypassing the mppt?)

Strange (variable) Absorption times/voltages. Are you using the recommended lithium preset?

I imagine the batteries LVD has kicked in, and the mppt simply has not raised the charging voltage enough for charging to resume.

What firmware is the mppt running?

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nicomauritius avatar image
nicomauritius answered ·

Hi Klim,

Thanks for your answer.

I cannot remember which firmware it was.

I didn't change any configuration. I only made sure that it was set for lithium settings and connected it.

Last time I connected to the mppt using a VE direct, it updated the firmware automatically.

Since than it has been working well.

When I see in the data that the max voltage of the day has been 14V, does it mean that the battery sensed the wrong voltage for a few seconds and shut itself down? Because the Mppt kept 14V in float mode at the battery terminals as long as the sun was shinning.









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