On 2024/10/12 at 12:11 AM, Dragan100 said:

I found some micro cracks in the joints on PCB around the 230VAC OUT filter, on Lout and also on Cout (picture attached).

Well done.

On 2024/10/12 at 12:11 AM, Dragan100 said:

Switching ON, everything OK! Firmware MCU display [U1 04.23] and for U2 no data on display?

You won't see the U2 firmware version unless there is at least about 5 volts more than battery voltage at the PV input. You could probably force the solar charger to "detect" PV and switch itself on; see the left side of SCC3.PNG here.

I don't have any 04.xx main firmwares in my collection, sorry.

On 2024/10/12 at 12:11 AM, Dragan100 said:

Without load, the Inverter has its own consumption of around 28W (LAB PSU display). With OUT[put] Load 100W light bulb => aprox. 125...130W is displayed on the LAB PSU display.

That sounds normal.

On 2024/10/12 at 12:11 AM, Dragan100 said:

I have to unsolder OUT C 10uF/350V, measure it, looks good and see what quality it is!

Could it be that the leads have tarnished, and you just need to clean the leads and resolder?

I've had it happen that capacitors "sing", yet appear to be working normally. I don't like that, so I replace them. These would be film capacitors. I would only replace it with one of the exact same capacitance, i.e. 10μF.

I clicked on the EPCOT link and it didn't respond in reasonable time; EPCOT, Panasonic, and Kemet brands should be fine, as long as they are film capacitors with appropriate AC voltage ratings. All capacitors of that size are likely to be film types. I don't expect the type of file (polystyrene, polypropylene etc) to be critical.

On 2024/10/17 at 6:54 AM, Coulomb said:

You won't see the U2 firmware version unless there is at least about 5 volts more than battery voltage at the PV input. You could probably force the solar charger to "detect" PV and switch itself on; see the left side of SCC3.PNG here.

I don't have any 04.xx main firmwares in my collection, sorry.

Hello @Coulomb and thank you for your reply,

I found a replacement for the Cout WIMA MKP4F 4.7uF/350VAC, installed it and tested the operation. It responds exactly the same as before with the original Cout, also after a certain time the output LC filtration starts to be noisy/"start singing". So the problem is most likely in the DC/AC drive.

Later, I was busy with other work, so the inspection of the Inverter remained on the second plan, and I did not work meanwhile on this topic. I need to bring an oscilloscope to look at OUT 230VAC Sine wave form and DC/AC drive signals, control voltages, analog and logic (+5VDC for logic, +/-(6...12)?VDC for analog...)

Meanwhile, I found a similarity of PCB construction in MPP PIP 3024HSE (3KW/24V, 50A PWM) model in some videos on YT. Flyback power supply section from BAT (like in yours SCC3.png) is copy-paste in this EASUN SPS3KW/24V/50A, also analog part with several TL074 around primary MCU, Opto ISO 350 + Floating power supply for drive IGBTs, placement of PV Charge section, heatsinks (find attach. in one of my previous posts)

Best regards = Lepe pozdrave = LP

Dragan

Edited October 18, 20241 yr by Dragan100

is this good enough for grounding ? Asking for a friend.

 

1 hour ago, BritishRacingGreen said:

is this good enough for grounding ? Asking for a friend.

 

Almost good enough cup grounding more efficient answer for your friend.

Helllo got 10 qmax inverters with cracked  varistors  number 

14k561

Cant find any in local market but 

14k471

 

Will they work ..?

They exist in input sction of mppt 

2 varistors 

The first end of the first variator is to  pv minus

The first pin pin of the second variator is to pv plus

The 2 remaining pins of both variators are tied together and to chasis ground 

Any idea about replacemnts

@Coulomb

 

 

22 hours ago, wael_fathe said:

Helllo got 10 qmax inverters with cracked  varistors  number 

14k561

Cant find any in local market but 

14k471

Will they work ..?

That sounds like you're considering lower voltage rated parts. I would not do it.

The PV inputs to ground is a weird voltage; I think one side has the PV  voltage added to a 50 Hz half sine wave or some such.

You'd have to check the voltage seen when operating, and extrapolate that to when max PV voltage is applied. At first glance, I wonder if 560 V standoff isn't even enough, and that might be why so many varistors have failed. Then again, a at another glance, they should only ever see bus voltage, so 560 V should be enough (and 470 V definitely too little). So maybe it was a batch of dodgy varistors.

On 2024/11/18 at 8:02 AM, Coulomb said:

That sounds like you're considering lower voltage rated parts. I would not do it.

The PV inputs to ground is a weird voltage; I think one side has the PV  voltage added to a 50 Hz half sine wave or some such.

You'd have to check the voltage seen when operating, and extrapolate that to when max PV voltage is applied. At first glance, I wonder if 560 V standoff isn't even enough, and that might be why so many varistors have failed. Then again, a at another glance, they should only ever see bus voltage, so 560 V should be enough (and 470 V definitely too little). So maybe it was a batch of dodgy varistors.

the  pv  positive input  is to one  varistor

the pv  minus   input is  tied to  other   varistor

 

the 2 left   alone  ends  of the  2 varistors  are tied to ground 

 

actually you commented that the pv  input  to ground  are wierd

yes they are  wired ...but  i didnt  say that

 

i find  a   part  have 20k560  on it  and installled it  the  first 20 is all about the diameter   the   most importnat number is the    560   ...thanks  for help mr  coulomb 

8 hours ago, wael_fathe said:

i find  a   part  have 20k560  on it  and installled it  the  first 20 is all about the diameter   the   most importnat number is the    560   ...thanks  for help mr  coulomb 

Yes the 20 is diameter in mm which is an indication of how much energy it can absorb and the 560 is the voltage rating. But be careful, with some brands the 560 needs to be read differently... it could be 56x(10 to the power of 0) which is 56V. For 560V the numbers would be 561. Check the datasheet to be sure. The voltage rating is normally AC_RMS  but can be either the nominal voltage or working voltage (definitions depend on manufacturer).  Again the datasheet will explain. Its a bit of a minefield.

On 2024/11/23 at 5:46 PM, Mach4 said:

But be careful, with some brands the 560 needs to be read differently... it could be 56x(10 to the power of 0) which is 56V.

Ah! Excellent point.

For a moment I wondered if that caught out the manufacturer's parts buyer, and that's why they all failed. But I think that with such a gross mismatch of rated voltage to actual voltage,  that they would not even pass whatever quick test that they do in the factory.

On 2024/11/23 at 9:46 AM, Mach4 said:

Yes the 20 is diameter in mm which is an indication of how much energy it can absorb and the 560 is the voltage rating. But be careful, with some brands the 560 needs to be read differently... it could be 56x(10 to the power of 0) which is 56V. For 560V the numbers would be 561. Check the datasheet to be sure. The voltage rating is normally AC_RMS  but can be either the nominal voltage or working voltage (definitions depend on manufacturer).  Again the datasheet will explain. Its a bit of a minefield.

thanks i checked both orginal and the one i installed rated 561   hope with this thy match

14d561k...burned

Tvr20561   replacment

 

 

Edited November 27, 20241 yr by wael_fathe

Hello. @Coulomb or @BritishRacingGreen  I have a question for you if you can help me with an opinion. I have a GROWATT SPF 5000 ES inverter that suffered a failure on the PV side, meaning that it had voltage spikes on the PV and went into failure with error 61. Upon checking, I found that the 7912 voltage regulator was defective and instead of -12VDC I had -13 or -14VDC. The problem is that after I changed this regulator, I somehow managed to drop some solder on one of the drivers that drives one of the IGBTs (L DN or N DN), it shorted out the driver output, and my house fuse tripped and I was left in the dark. After replacing this driver, I found that the inverter works perfectly when I connect a power source instead of the battery, it generates a 230VAC output, but if I connect the inverter to the 230VAC input using a current-limiting bulb, the bulb lights up as if the inverter has a short circuit. I checked everything, I didn't find any short circuit, but that bulb always lights up and the inverter doesn't work. Is it normal for that bulb to light up, and should I risk running the inverter directly on the network, without that bulb? Or does the inverter still have a problem?
I'll attach a few links where I filmed how it behaves only on battery or only on AC. On battery, you can clearly see how PWM works, but on AC, PWM only comes into action for a fraction of a second when it switches the relays.

 

 

 

 

 

 

 

 

 

Edited November 28, 20241 yr by octavgeo

1 hour ago, octavgeo said:

if I connect the inverter to the 230VAC input using a current-limiting bulb, the bulb lights up as if the inverter has a short circuit. I checked everything, I didn't find any short circuit, but that bulb always lights up and the inverter doesn't work. Is it normal for that bulb to light up, and should I risk running the inverter directly on the network, without that bulb?

As soon as the inverter draws power, the bulb lights and the AC voltage goes out of spec.

Can you test with a higher wattage bulb?

I assume that you have no AC-out load.

I don't know the Growatts at all, but they seem vaguely Axpert-like. Is it possible that a movistor or capacitor has shorted after the "safety" (AC-in) relay(s)? In an Axpert, there are two AC-in relays, in the live and also the neutral circuits.

Does the solar charger definitely work now? Sorry, I only briefly checked some of the videos. I'm thinking that perhaps a lingering fault in the solar charger is causing big current draw when the AC-in neutral relay comes on. Remember that  PV in minus is usually BUS-, and BUS- has a large potential compared to ground and therefore AC-in neutral.

Check for shorts from PV- and PV+ to earth.

55 minutes ago, Coulomb said:

As soon as the inverter draws power, the bulb lights and the AC voltage goes out of spec.

Can you test with a higher wattage bulb?

I assume that you have no AC-out load.

I don't know the Growatts at all, but they seem vaguely Axpert-like. Is it possible that a movistor or capacitor has shorted after the "safety" (AC-in) relay(s)? In an Axpert, there are two AC-in relays, in the live and also the neutral circuits.

Does the solar charger definitely work now? Sorry, I only briefly checked some of the videos. I'm thinking that perhaps a lingering fault in the solar charger is causing big current draw when the AC-in neutral relay comes on. Remember that  PV in minus is usually BUS-, and BUS- has a large potential compared to ground and therefore AC-in neutral.

Check for shorts from PV- and PV+ to earth.

I'll try a higher power bulb. The one in the video already has 250W. I'll probably put another 250W one in parallel. The 20uf 350VAC capacitor right after the last relay is not shorted. GROWAT really looks very similar to Axpert, it only has small differences. I also thought that it's possible that there's something wrong with the charging circuit. On the other hand, maybe that's how the inverter behaves, drawing a higher current at startup before the PWM starts and controls the IGBT from DC-AC. I'll probably try to start it without bulbs, and put a 10A automatic fuse and maybe that fuse will just trip...

On 2024/10/18 at 6:03 AM, Dragan100 said:

Hello @Coulomb and thank you for your reply,

I found a replacement for the Cout WIMA MKP4F 4.7uF/350VAC, installed it and tested the operation. It responds exactly the same as before with the original Cout, also after a certain time the output LC filtration starts to be noisy/"start singing". So the problem is most likely in the DC/AC drive.

Later, I was busy with other work, so the inspection of the Inverter remained on the second plan, and I did not work meanwhile on this topic. I need to bring an oscilloscope to look at OUT 230VAC Sine wave form and DC/AC drive signals, control voltages, analog and logic (+5VDC for logic, +/-(6...12)?VDC for analog...)

Meanwhile, I found a similarity of PCB construction in MPP PIP 3024HSE (3KW/24V, 50A PWM) model in some videos on YT. Flyback power supply section from BAT (like in yours SCC3.png) is copy-paste in this EASUN SPS3KW/24V/50A, also analog part with several TL074 around primary MCU, Opto ISO 350 + Floating power supply for drive IGBTs, placement of PV Charge section, heatsinks (find attach. in one of my previous posts)

Best regards = Lepe pozdrave = LP

Dragan

for  your  information this model  have great tendency for its   output capacitors  to be  completely open  with  only 10mf  instead  of 470mf //....micro farad i mean  by the "m"

hello  @Coulomb am stuck with  a  unit that have only 2 sps

one is  battery sps   12+  12-  5vdc or  mains sps 

and the other is  the  soft start 

 

the unit is 24vdc   and the sps  turned off   due to short  in the  2sa1020

drive  npn 

 

even  after replacement 1020npn    the  12-125   sps is dead 

 

i reached stage where i have to replace  the transofrmer   as  i tested  all   othger components  ...can i get this transformer from other units that is not 24vdc 

 

my unit's main sps  uses 24 from battery directly   via  steering diode 

the  donor unit is 48vdc worest its mains sps transformer is not fed from 

battery but rather from  battery sps  that generate around 100to 120vdc

they look  physically  the same  am not sure  what to do  

 

one x trasnsormer  fed from 100 

on  fed from 24 

both produce the same  vdc  and have  same look

may be  they the same if the  maker  change the frequency of operation  

to compensate for different in the input dc???

On 2024/12/10 at 9:19 AM, wael_fathe said:

this model  have great tendency for its   output capacitors  to be  completely open  with  only 10mf  instead  of 470mf //....micro farad i mean  by the "m"

The output smoothing capacitor (the "C" of the "LC filter") is only about 10-20 μF (for 3-5 kVA models); these are large rectangular film capacitors, non-polarised. Did you mean the bus capacitors (typically 2 x 470μF for 5 kVA models, polarised), or confusing the two, or... ?

3 hours ago, wael_fathe said:

even  after replacement 1020npn    the  12-125   sps is dead 

I believe that the 2SA1020 is PNP. 

3 hours ago, wael_fathe said:

i reached stage where i have to replace  the transformer   as  i tested  all   other components  ...can i get this transformer from other units that is not 24vdc 

Almost certainly not. My understanding is that most of the time this power supply operates on battery voltage, so that would be twice as high on the 48 V models. These circuits can operate over a wide voltage range, but I don't think that wide.

Have you replaced the SG3525? Also check for bad solder joints on the tiny capacitors. I had a King 5 kW that had the timing capacitor intermittently open circuit. Also check the larger chip capacitors out of circuit; those things are barely able to be called capacitors, and can drift and change capacitance with applied voltage. The larger valued ones (usually only used for bypassing) are the worst, as they need the more extreme permittivity materials, which have the worst parameter spread.

16 hours ago, Coulomb said:

The output smoothing capacitor (the "C" of the "LC filter") is only about 10-20 μF (for 3-5 kVA models); these are large rectangular film capacitors, non-polarised. Did you mean the bus capacitors (typically 2 x 470μF for 5 kVA models, polarised), or confusing the two, or... ?

I believe that the 2SA1020 is PNP. 

Almost certainly not. My understanding is that most of the time this power supply operates on battery voltage, so that would be twice as high on the 48 V models. These circuits can operate over a wide voltage range, but I don't think that wide.

Have you replaced the SG3525? Also check for bad solder joints on the tiny capacitors. I had a King 5 kW that had the timing capacitor intermittently open circuit. Also check the larger chip capacitors out of circuit; those things are barely able to be called capacitors, and can drift and change capacitance with applied voltage. The larger valued ones (usually only used for bypassing) are the worst, as they need the more extreme permittivity materials, which have the worst parameter spread.

i  replaced  a;1020 5526  transistor  ...sg3525....and even tested the uc3845  in circuit  it works and osillate 

at 100khz   

the main symptom is that  the main sps  restarts or shut down  at the moment  sg3525  work 

so  i  though  i am smart   i tried to dissconnect   4 drive transistors   of 1020 5526   each time  discconct 4  

the  first 4  are for  igbt dc-dc 

the second 4 are for mosfet dc-dc

when i disconnect the  fets 4  driver 

the igbt's  driver blow and the screen faded 

i get the  transformer out it give me zero rings on my ring tester  used for testing such  high frequency  

so time to replace  the transformer   as i tested  every thing else  in the board

 

thanks  for the info   i will haunt for  24  transformer  

 

as for the first question yes the bus  caps 470mf    some models have  bad  caps  probably  so cheap 

that they  only  measure  10nf  or so  ,,,,

 

5 hours ago, wael_fathe said:

i get the  transformer out it give me zero rings on my ring tester  used for testing such  high frequency  

so time to replace  the transformer   as i tested  every thing else  in the board

Zero rings sounds like it's open circuit (or you tested the wrong pairs of pins). If the transformer is open circuit, I can't see how that would shut down the power supply when the 3525 is enabled. [ Edit: Though maybe your tester is testing for shorted turns, and rings in the case of no shorts. ]

Did your tests include the small MOSFETs (UT304G) across the outputs of the NPN/PNP push-pull pairs? If these are shorted or not turning off, that might cause the power supply collapse.

Edited December 12, 20241 yr by Coulomb

On 2024/12/11 at 6:51 PM, Coulomb said:

Zero rings sounds like it's open circuit (or you tested the wrong pairs of pins). If the transformer is open circuit, I can't see how that would shut down the power supply when the 3525 is enabled. [ Edit: Though maybe your tester is testing for shorted turns, and rings in the case of no shorts. ]

Did your tests include the small MOSFETs (UT304G) across the outputs of the NPN/PNP push-pull pairs? If these are shorted or not turning off, that might cause the power supply collapse.

UT304G  no obvious short across those  unless they fail in wierd way  

On 2024/09/20 at 7:06 AM, wael_fathe said:

My initial guess is bad output cap...as ripple increase due to largeload....cap fail to supress them...one spike registered as high voltage....very logical ...

 

 

This model is for a company...installation company i repaired 10 pces they all ok...however this one only have problem ...i also suspect the input fets...as all first 9 pces all repaired with hy3712  super solid chinrse fet...

But this last is mixture of hy3712..and 85h160 fet that i survived from bad inverter

So i guess there sort of unbalance creating the wavform in the primary due to may be diffeent threshold on voltage

 

Just a guess based on practical clue...with9 pcea working and one not

my guess  failed  i replaced the caps and   the  fets  no avail

On 2024/12/11 at 6:51 PM, Coulomb said:

Zero rings sounds like it's open circuit (or you tested the wrong pairs of pins). If the transformer is open circuit, I can't see how that would shut down the power supply when the 3525 is enabled. [ Edit: Though maybe your tester is testing for shorted turns, and rings in the case of no shorts. ]

Did your tests include the small MOSFETs (UT304G) across the outputs of the NPN/PNP push-pull pairs? If these are shorted or not turning off, that might cause the power supply collapse.

solved  the  lm7912   was  shorted   despite teh fact that no  clear short was detected  

yet the replacement of which brought the smps back to work again  

On 2024/12/22 at 3:59 PM, wael_fathe said:

my guess  failed  i replaced the caps and   the  fets  no avail

failed    all i did failed  still error  08  roaring after  2k load  next step   i will  replace the  control board  every  body stay tuned

@wael_fatheIs the inverter stable when on and no load?

Is the 08 an bad reading or is the DC bus voltage going too high?

I have previously repaired a 08 error by replacing the small ceramic capacitors on the output circuit of the SG3525 which feeds the DC-DC IGBTs.

7 hours ago, Shadders said:

I have previously repaired a 08 error by replacing the small ceramic capacitors on the output circuit of the SG3525 which feeds the DC-DC IGBTs.

Interesting. Are these the capacitors in series with the transformer windings? With a diode across them?

Hello, I have such an inverter. Probably Axpert vm III 3kW. I only use it as an offgrid with 9 panels. I don't know exactly what time it was, but when I came back there was error 51 on the screen, so I turned off the inverter and after restarting it was 09. I took it apart and found 3 elements, one of which looked like a diode and had completely evaporated If anyone has photos or numbers of these elements, I would be grateful for help. I didn't record any short circuits, so maybe it's just the fault of too strong sunlight and unchanged current setting because the firmware is from a similar 4kW model and solar charging was at 60A for the battery which I forgot to change and when the sun came out today, it could have happened.