SPF5000ES powers only with battery issue

[R D]

Hello.

Inverter variant with firmware 040/041.
Starts only if battery is connected.
With grid connected, solar active in daylight, if the battery is disconnected, it turns off.

The inverter works well otherwise, no issue with charging Pylontech from solar/grid and pull up to 6kw from panels.
12.8MWh harvested in 20 months.

After further investigation, finds out the auxiliary switching power sources are broken.

These aux PS are located on the MPPT board.
One gets voltage directly from AC input.
The other one gets voltage directly from the solar input.

No visual/smell sign of burned component (transistor, diode, resistor). All diodes seems ok after a brief check with multimeter, the NPN and N-MOS transistor verified ok.

Any help is appreciated.
A schematic would be very helpful.

[amos]

have you checked 2845 power chip ? You can use multimeter to test earth pin with other pins and see if there is short circuit.

[R D]

The chip remained at end for check.
I succeeded to clean the protective varnish from the top.
The name is hard to guess.
But you named it 2845.

Thanks

I will come back with feedback.

• This reply was modified 4 months, 1 week ago by R D.
• This reply was modified 4 months, 1 week ago by R D.

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