I have repaired 2 units with the same failure..1 FET plus Varistor. You have to take out that long big double coil..down under this coil is a another board with a burned connection on copper strip line (due to a weak metalized connection )

Check the Fets /Igbts of the full bridge on the output, often these fail due to overvoltages on the ac grid and sometimes tend to kill the Fet driver, too. You can also check whether there is any over voltage sensing after the boost converter, I got one which tries to put a sinusoidal current into the grid but if you disconnect the ac line while operating it increases its output voltage up to self destruction trying to reach its intended current (there is no voltage feedback on mine). Check the zero cross detectong section, too (probably optocoupler + sone zeners). Btw the topology on mine was DC input -> boost converter generating an indermediate voltage with sinewave envelope, synchronized to the grid -> full bridge for changing polarity (dc to ac)

Thanks for the clear videos and documentation. Wish you could find the root cause... With the transformer being so hot, maybe the enamel has melted and it is shorted?

I bought like these secondhand hope they work fine. They have black;yellow;green output wires. Green for earth; black for live and yellow neutral? Can you please help me? Thks.

By law, Microinverters do not produce any power unless there is presence of a grid... This is called anti-islanding and is supposed to protect line workers in case of power outage at the grid. They do not want microinverters (or string inverters for that matter) back powering the grid if someone is working on it.

i think i may know your description lacked something that i think i saw in the design it has 3 stages not 2 stage1 is the DC converter (600V DC supply) stage2 "buck converter" isnt a buck converter at all its a classD chopper producing what would look like full wave rectification of the AC line stage3 is the 4 FETs it chops the 100hz wave into the 2 halfs of the 50hz AC output note that stage2 and 3 need a sample signal to mirror the bad diodes you found must be 1KV or higher due to the 600V expected output i suspect the chopper circuit is not getting a proper control wave or the FET is not switching properly

@thecaptain8773

4 жыл бұрын

Nobody responded to this but I think you got it right. Microinverters do not produce any power unless there is presence of a grid...

if there not connected to 220 they will not produce power

Question please, there are a number of Enecsys SMI-263-72 Micro Inverter available on Ebay, in your opinion, what would be the odds they may have similar issues? thank you.

@PowerElectronicsBlog

7 жыл бұрын

Pretty much 100% chance of early failure. All of their microinverters die early, it's well-known and well-documented that they do.

@ReverendRichie

7 жыл бұрын

wow and thank you. By chance, do you know what version this problem was fixed? Thank you for your fantastic work here, saved me lots of headaches.

@PowerElectronicsBlog

7 жыл бұрын

Enecsys went bankrupt. This was never fixed.

@ReverendRichie

7 жыл бұрын

Wow and Thank you very very Much!!!

Wat je kunt proberen om de levensduur van het paneel in deze toestand te vergroten is om de voorkant te behandelen met een waterdicht transparant materiaal. Blanke lak misschien? Of gewoon een extra stuk glas er overheen welke je langs de randen in kit legt. Uiteindelijk zal er wel vocht in komen en corrosie de boel gaan verzieken, maar als je dat kunt uitstellen heb je er misschien voorlopig nog wat aan.

@PowerElectronicsBlog

8 жыл бұрын

Zat ik inderdaad ook aan te denken. Het is alleen de vraag hoeveel moeite ik er echt in moet steken; zonnepanelen kosten tegenwoordig niks meer, je krijgt een paneel als dit in goede staat tweedehands voor 70-80 euro op marktplaats. Om er dan een glasplaat+kit+sealant van ~20 euro op te smijten als hij dan alsnog over 2 jaar stuk is...meh. Voorlopig is het gewoon nog een testpaneel voor de inverters die ik aan het bouwen en repareren ben, daarna kijk ik of er een goedkope manier is om hem voor een jaartje te dichten.

@pcmadmann

8 жыл бұрын

Heb je helemaal gelijk in. Een spuitbusje blanke lak van de Action dan. Kost €2 misschien? Vraag is alleen hoeveel de transmissie is van de lak.