few years on..

Hi all, I have 48v 5kw fivestar working well for last 3 years.

Last night we had eskom.power failure, inverter ran until.bat. voltage dropped to 45.5v. at 1am.

No way I can restart the inv., - error 03. I managed to charge bat. direct from pv through series resistor at 10A ( but not much sun today.)

Bat. voltage currently at 48.6v. What should min. startup voltage be? Or did eskom break my inv. when power went off at 1am?

Same thing happened a few weeks ago but I managed to restart inv. after a few tries - I do not remember what bat . voltage was.

2 hours ago, Beugleuce said:

few years on..

Hi all, I have 48v 5kw fivestar working well for last 3 years.

Last night we had eskom.power failure, inverter ran until.bat. voltage dropped to 45.5v. at 1am.

No way I can restart the inv., - error 03. I managed to charge bat. direct from pv through series resistor at 10A ( but not much sun today.)

Bat. voltage currently at 48.6v. What should min. startup voltage be? Or did eskom break my inv. when power went off at 1am?

Same thing happened a few weeks ago but I managed to restart inv. after a few tries - I do not remember what bat . voltage was.

Are you still without power from Eskom?

I would guess the batt voltage is too low to restart if no grid. Only knowing what your inverter settings would it be easier to give guidance.

On 2026/04/13 at 11:40 PM, Beugleuce said:

Bat. voltage currently at 48.6v. What should min. start-up voltage be?

48.0 V should definitely enough to start the inverter, e.g. LEDs showing.

Fault code 03 for Axperts usually means battery voltage is too high. But Fivestar inverters are generally clones, from memory and a quick search. So they may be running modified firmware, or their own firmware. Or it might suddenly have decided that it's a 24 V model.

Are you seeing 48.6 V on the inverter screen or via monitoring software? If so, then the inverter is on, but there may not be enough energy in the battery to allow the actual DC-AC converter to start.

Are there LEDs on that indicate that the battery is being charged?

The below shows a Fivestar inverter measuring too high a voltage. If this is the case, it's possibly just the sense resistors, an easy fix if you are handy with electronics.

Edited April 17Apr 17 by Coulomb

12 hours ago, Coulomb said:

Hi, thank you for the reply.

I have measured 48.6v bat . with multi meter, inverter lcd showed 120v.

Following recommendations on this forum re. replacing caps at the psu, the inverter is now working fine.

Someone quoted between R400 to R2700 to fix, glad I fixed it myself. What bothers me though, I replaced the caps 2 years ago due to lcd cycling (to Rubycon from the factory fitted Yst), .This time around I could not find Rubycon, had to buy Hitano , went for the exr series which is low esr. I have now changed the 16v ones to 25v .

I replaced 8 caps in total(just in case) - c78,c79,c95,c132,c116,c75,c69,c7

Hopefully I will have another 2 years of joy from the inv.

12 hours ago, Coulomb said:

48.0 V should definitely enough to start the inverter, e.g. LEDs showing.

Fault code 03 for Axperts usually means battery voltage is too high. But Fivestar inverters are generally clones, from memory and a quick search. So they may be running modified firmware, or their own firmware. Or it might suddenly have decided that it's a 24 V model.

Are you seeing 48.6 V on the inverter screen or via monitoring software? If so, then the inverter is on, but there may not be enough energy in the battery to allow the actual DC-AC converter to start.

Are there LEDs on that indicate that the battery is being charged?

The below shows a Fivestar inverter measuring too high a voltage. If this is the case, it's possibly just the sense resistors, an easy fix if you are handy with electronics.