razmasoom

May be I own a clone one and its using stgw80h65dfb. But i have watched many videos and forum , they are using it . I think irgp4066 has been obsolete and no longer manufactured. Others may confirm usage of 80h65 in their inverter (genuine)

Can anyone confirm the value of capacitor c4 and C110 out of the circuit. As mentioned in schematic it shows 10nf and both are in parallel. But when i made a test circuit for sg3525 and other the frequency not outputting around 38kHz rather it shows around 7kHZ . but when putting 2.2nf (as have in stock ) ie. total 4.4nf (as both are in parallel) almost reach around 28kHZ and are accordance 2F = 1/{0.7 * 3[R(d)] * R(t) * C(t)} .I have already assembled the unit of mine and is on running condition , so cant test out of circuit. it should be near 1.7-1.8nf i think.

Sir but presently most of inverter do coming with STGW80H65dFB ( 10524pf)which has obviously higher capacitance then earlier used irgp4066d(4440pf).

I think selection of replacement IGBT and MOSFET is only dependent on dead time between the pluse generated from sg3525 ic in output A and output B. I think all igbt/MOSFET suited for replacement if turnoff time is below the dead time of pulse (out A and out and its doesn't matter what's is it's capacitance characteristics.

check and change the pnp and npn transistor in dc and igbt drive section. Hope will resolve your problem. Due failure of one of transistor (partially shorted) leads to such type issue. Will work flawless in solar directly as it charges the big capacitor near 380-400v. Also check three pin BAT schotkey diodes and always check for the resistance in igbt and mosfet side. Change if not in range. look for any broken path ie, track, dry solder joints etc.

Try electric manual desoldering pump .. it work great and it's cheap then soldering iron 😅

You may check for voltage across the big capacitor , is there any large drop in voltage then there is drive problem in DC/Buck section If slight drop then Check optocoupler for output igbt (most probable).

i attached to secondary after diode point and -12v regulator using two external 12v 2amp smps in series to make dual power supply to test the board. Any shorting makes the smps to stop its output. During this i used thermovision camera to look out any shorting component.

Update: I changed the cap c132 with slightly lower esr capacitor. Earlier was having 0.31 ohm now replaced with 0.21ohm( one found in lot after testing all capacitor with ESR meter ) . Now inverter starts with 60v and settles to battery voltage 54v. Now no error pops up. Ordered some low esr capacitor to try next. Thanks for your research its only -12v which effects the inverter battery voltage sense apart from the resistor bank for battery voltage sense.

originally it was not there ..but temporarily i soldered by seeing the schematic, thought it may be the cause for not interchangeablity for SG3525A, U3525A and KA3525A. But later i found that my drive transistor getting short . Initially i thought may it was due to custom gate drive transformer. Changed it several time using different thickness and turns to bring primary inductance and resistance to orginal. Struggled alot . Lastly i realised that shutdown pin component which i additionally put was making q60 and q61 mosfet on which was leading high current through the drive transistor above there rated capacity of 2amp. Burned almost 100 transistor to found the culprit which i installed and it shouldn't be there :). Finally removed the r15 and C108 and everything become normal but later E03 error haunting me. Your post suggested for -12v rail failure showing 120v but in mine case its not going that high but around 90v and that too not steady and settles to battery voltage buts its take time. May be in first start inverter gets off before voltage comes in range. When starting for second time or third time by disconnecting the battery battery voltage drop from almost the last recorded voltage and finally inverter starts if voltage goes below 60V.

tried with KA3525A but no change. Error at starting 03 and which goes away after some time. i do have U3525a ic too. will try with that too. Sir could you share the post link so i can study it for better understanding. Thank you

checked and resolder as if any dry joint may cause the issue but still same. Will definitely try with the higher capacitor value as suggested and will report back . Thank you for quick response sir.

No sir , Earlier I thought same , checked with ESR meter , was showing around 100uf and low loss. So I re-soldered it as currently i don't have Low ESR capacitor in stock.

Hello sir , i am recently facing the Error 03 , battery high voltage error. Measured with multimeter reads 54V but inverter shows around 90V which gradually come down and inverter starts outputting 230V ac. Recently changed the -12v regulator and capacitor c132 (general capacitor). All +12V (around 12.04v) ,-12 (11.95v) and 5v (5.01v) seems ok. What could be the problem. Do i have to use low ESR capacitor. I also checked R29-R32 and R36-R33 ,seems ok. But in R36-R33 section total resistance value shows around 3.7M which gradually increases to 3.87M while in R29-R32 section it shows 3.95M without fluctuating. I individually checked after de-soldering but seems fine. Lastly interchanged the resistor form R29-R32 and R36-R33. But same result, showing fluctuation in negative side value. (Checking with control card removed). Checked the OPAMP and its surrounding components i.e. resistor and capacitor in control card all seemed ok. Any ideas where to look. Recently changed the gate driver transformer ( self wounded in toroid core). Also changed KA3525 IC with SG3525 . all waveform looked ok. Also changed c141 and c20 (thought it may be dropping the voltage of -12v). Earlier I used to get -12.05v but now its showing -11.95v , checked with thermo-vision camera only showed max heating in 5v regulator and c27 . Changed the C27 too. Earlier facing some noise in IC side , thought I may be due to ringing in gate drive transformer ( During dismantling of it for calculating winding turns bobbin broke :)) . But latter found the one Q15 was slightly heating which was causing the noise. Replaced all driver transistor . Now all is Ok. no heating.

Hello @BritishRacingGreen can you share waveform of primary side and secondary side of gate drive transformer tx5,tx8,tx10 and Tx11 in dc side and buck side igbt showing peak to peak voltage. Facing some ringing in igbt side.