MPPT 100/30 in bulk mode but not charging

DIY
,
1

Since a couple days my mppt is not charging my battery.

I have a 200ah Lifepo4 connected on a mppt 100/30 with 3 x 200w solarpanels. I have enough voltage on the solar side but current and watt stays at zero.

Any idea what could cause this problem ?

Screenshot_20260529_145649
Screenshot_20260529_145649904×2316 117 KB

2

Please can you post your MPPT settings.
possible causes: Incorrect settings - ABS,FLoat voltage set too low.
Blown fuse - MPPT battery voltage different from actual battery voltage
BMS for battery not accepting charge.

3

Hi mike thnx for your reply , these are the settings. It worked behoren but dont know what could cause this

Screenshot_20260529_222453
Screenshot_20260529_222453904×2316 160 KB

4

Those look ok,
Please can you give a translation of status “Aan”?
If the unit has a load output, what happens if you connect a load? (20 - 40W). Do you see load current? does this come from the battery or from solar?
Measure the battery voltage at the MPPT terminals, and at the battery terminals. This is beginning to look lie a blown fuse / dirty connection somewhere.
It may also be possible that the battery may not be accepting load, but I would then expect to see the indicated voltage equal to the float voltage.

5

How long has the set up been in place?

If it is a new set up check your pv polarity. It is possibly backwards.

6

The status “AAN” means ON .

I have measured at the terminals and I measure 16.1v at battery side and 78.9v at the solar side on the solar charge controller

On the battery itself it says 13.3v.

Between the solarcharger and the battery I also have an batteryprotector

7

No not new been running very good for like a year but only since a couple days it won’t produce

8

If tou are measuring 16v at the mppt but 13v at the battery then the device in the middle has failed most likely.

9

Yup I just removed the battery protect and start working again.

Is it even necessarly to have a batteryprotect between the battery amd charger?

Screenshot_20260530_142722
Screenshot_20260530_142722904×2316 121 KB

10

It is a good idea, but not essential to have a battery protect between the charger and the battery. However, this can only be omitted IF

  1. The battery has an internal BMS that can disconnect on over voltage OR
  2. The BMS communications controls the charger remotely.

IF you are measuring 16V on the output of the MPPT, then the Battery protect may have shut down from overvoltage.

11

Yes my battery has an internal BMS . I measured again at the terminal of the mppt again now at the battery side and it’s in the 13v again.

Thnx for the help