Reliable pure sinewave inverter replacement parts query

Fabian
Fabian Registered Users Posts: 131 ✭✭
I have a reliable 24v 3000watt 120vac pure sinewave inverter and  one of the diodes need replacements.  It is labeled D13 on the circuit board. Because it is so small and fractured i cannot read the value on it.
Is it possible you could tell me what diode to use or is it possible for me to just replace the 4 diodes that are in that section ( D2, D5, D12, D13) with regular barrel shape diodes? If yes what value diodes I should use for each of them? or basically i could use just 4 same small barrel diodes and which position is the correct way to place them in the circuit?

I upload some pictures of where on the board they are located and the model inverter that i have.

In the pictures they are located to the left side beside the brown filter caps. You can zoom in to get a better view of them and the 4 mosfets that are located there too.


Comments

  • mathias
    mathias Registered Users Posts: 31 ✭✭
    Hi Fabian,
    Reliable has been unwilling to respond positively to my warranty claim (18 months warranty, and my problem happened at 15 months... It was too close to 18 months for them !!! Crazy...)
    Still, they were ok to sell me parts or board, they even offered me a 5% discount on a new inverter ! Thanks, i changed brand (yes, i'm not lucky with warranties...)
    All this to say that they will probably respond if you ask them.

    Good luck

    Mat

  • Fabian
    Fabian Registered Users Posts: 131 ✭✭
    Here is a link with the photos.
    Any help would be greatly appreciated.

    https://www.fieldlines.com/index.php/topic,149996.0.html
  • Fabian
    Fabian Registered Users Posts: 131 ✭✭
    i got a reply from reliable company saying that the replacement is 1N4148. I am wondering if i can replace all 4 diodes in that section with the same #? what do u think?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    It depends on what failed....  Frequently, something else failed, and that failure takes out the gate drive circuitry.

    Would it hurt to replace all of the l those diodes, probably not (if you are careful. Surface mount components are pretty easy to break when hand soldered).

    Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Fabian
    Fabian Registered Users Posts: 131 ✭✭
    I notice that when i turn on the inverter, the driver board inside the inverter has a red light flashing instead of a steady red light which would suggest that something is wrong i presume. 

    I see the input voltage on the inverter display but there is no output voltage display and when i test the output i am getting around 18vac instead of 120vac. 

    Please tell me what could be the issue(s) and which parts would need to be replaced.
    I anxiously await your feedback.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    You can look around for how to test a FET... Such as this (assuming those are power FETs of some sort):

    https://www.electro-tech-online.com/threads/testing-fets-in-circuit-with-an-ohm-meter-and-an-external-dc-power-supply.139192/

    You have multiple FETs/power transistors--You can use an Ohm meter to measure gate/source/drain resistance... And if one is "different" from the rest, that guy may be the problem (or its driver circuit).

    Problem is, without a parts list and a schematic, it is difficult to guess what is affecting your readings the most (the "FET" or the components around the FET).

    If you can get a replacement board at a reasonable price (shipped to Jamaica?), that may be the place to start.

    I do not know enough about inverters to debug any "blind" or from my keyboard.
    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • solarpvlabelsdotcom
    solarpvlabelsdotcom Registered Users Posts: 3
    It depends on what failed.
    Frequently, something else failed, and that failure takes out the gate drive circuitry.
    Solar Placards, Solar Plaques, Solar Labels, Warning Signs.
    Fast Custom Service, No MOQ, Express to office Door-to-Door.
  • Fabian
    Fabian Registered Users Posts: 131 ✭✭
    I check the fets and them gone bad. The part number is IRFP4368. Can't get any in Jamaica. Can someone please tell me a replacement/eqiuvalent one for that number. Let me try and see if the one(s) that you state that can replace it  probably is in Jamaica.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Digikey is a common mail order supplier:

    https://www.digikey.com/products/en?keywords=IRFP4368

    They are around $6.50 each in small quantities...

    Crossing to another "similar" part may not be available/work with the existing drive circuit(s). The drive circuits are pretty much matched to the exact transistors. "Crossed" parts may not be "closer enough" to function correctly.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Fabian
    Fabian Registered Users Posts: 131 ✭✭
    edited January 2020 #11
    would any of these be equivalent to use?
    IRF4110
    IRFP064N
    IRFP260N
    IRFP460
    IRFP250N 
    IRFP140
    IRFP9140
    IRFP9240
    IRFP450