DaveS

Good day All. I have a synapse 7.2 Kva inverter for repair that came in with almost all the HY3215 physically blown apart (the 12 fets connected to the 48v rail) It appears the battery was connected with reverse polarity. After replacing these, several smd resistors and a faulty control card (sourced from a scrapped inverter) there was a F09 error after replacing the 12 FETs,the inverter seems to work as it should including charging the battery from AC mains and PV. The 3 low voltage secondary smoothing caps that commonly fail have also been replaced (for the pos and neg 12v supply) The issue I cannot resolve is that even with the AC grid charging disabled and no load connected,the inverter consumes over 10 amps from the AC mains supply. When connecting mains power the inverter consumes the normal 2 or 3 amps for a short time then suddenly jumps to over 10 amps,I do not smell any burning or feel any component or heatsink unusually hot. I have checked all the FETs and IGBTs as well as the bipolar capacitors around the buck regulator and full bridge transistors. The bus voltage does not decay quickly after powering down so I do not believe there is a low resistance fault here that may be causing this excessive power consumption. Has anyone had such an issue before and can help to resolve this ? Cheers

Thanks Coulomb, Will do further voltage checks.

Good Day Chaps, Can someone point me in the right direction please. I have this AER Power inverter Model: M5000H-48P 5kW inverter,all FETs and fuses are intact. The inverter powers up from battery supply or AC mains,fans run at full speed and the LCD displays battery SOC as OK otherwise all values as zero,after the screen test,even when scrolling through the menu options. All 3 LEDS above the LCD are out and no fault code is shown on the LCD. The 3 power rails,where the smoothing caps often dry up,are at 12v,10v and -16v,scope showing negligible ripple and caps are testing OK. Output of the 5v and -12v regulators are good. No obviously burnt components on the main board or control card. I can post pictures if that will help. Any idea where else to look ? Cheers.

Thank you @Coulomb Will try your tried and tested method .

A question for the chaps repairing inverters. I have a 1kVA fivestar UPS/inverter with shorted H bridge IGBT transistors after customer tried to power an undersink water heater and kettle at the same time. I would like to test the drivers before replacing the IGBT's. What is the best way to do this ? Can I scope the gate drive waveform with the IGBT transistors out or is there a better way to test them ? Thanks

Good Day All, Some advice please,I have a CB Solar synapse 4.0+ with a flashing LCD brought to me for repair. I replaced the 5 smoothing caps,some were bulging, in attached picture. The inverter powers up now with no errors on LCD but charger LED stays off with no charging voltage going out the battery leads,not sure if this can be disabled in setup ? It worked in tandem with a second inverter and shows H5 on LCD. Something else I noticed is the large heatsink on the left hand side in the attached picture is running quite warm even while only passing the mains supply through the inverter. All other heatsinks all stay cool. Inverter does start up on mains fail. Is this normal or does it sound like there are further faults ? TIA

Have spent quite a bit of time with my meter on "continuity" working out what is connected to where ! Will check the files section for schematics. Thank you

Good day all, I have a voltex 12v 1kVa inverter that seems fully functional except the battery is not being charged while mains is available. The negative wire from the secondary winding of the charging circuit was loose and could have made contact with the PV +ve terminal (See circled lug in attached picture) There does not seem to be a soft start psu,even if there was,it would appear to be working as the LCD shows normal display with a flashing green charge LED(not sure if that is normal) Fault LED not lit. The system psu seems to be at top right of PCB(circled) has output voltage and the SMD 7805 output voltage is stable. Checked the rectifier on the secondary of what I think is the charger transformer(bottom left of PCB),tests OK. No other obviously damaged semiconductors,replaced the through hole UC3845,near charger transformer,as a guess with no change. Can anyone help with a tip where/what to look for please ? Is there a way to "factory default" these inverters ? That seems to resolve many software issues on other electronic equipment I have worked on.