Trying to determine NPN or PNP in a circuit

Discussion in 'OnBoard Electronics & Controls' started by sdowney717, Nov 2, 2012.

  1. Don H
    Joined: Apr 2012
    Posts: 52
    Likes: 4, Points: 8, Legacy Rep: 45
    Location: Queensland Australia

    Don H Junior Member

    If you were paying labour for a shop to fix it then it wouldn't be worth the trouble but since you are going through it step by step then you will probably will come out ahead. It looks like all of these are available from Element 14/Newark. I didn't check Mouser but they probably have them as well.The irf1010 drops to $1.59 once you get 10 of them so i'd still be putting new ones in. They will deliver to your door so that will save you drive time and fuel and you can order on line.
    Good luck

    Thanks Don
     
  2. sdowney717
    Joined: Nov 2010
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    Location: Newport News VA

    sdowney717 Senior Member

    I checked the good mosfets and with 4.5vdc on the gate, they turn fully on, measuring drain to source forward and reverse polarity of 0.1 ohms.

    I am ordering most parts off Ebay, the IC's were $1 each piece good deal, IMO.
    I was surprised how much more the PNP transistors are. Paid $10 for a lot of 20 2SB892. The 2SC3205 were 10 for $4. Had to buy more to get better deal. anyway maybe I can use extras on something else.
    I got 10 IRF1010E for $7.
     

  3. Duane P Wetick
    Joined: May 2013
    Posts: 12
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    Location: Erie, PA

    Duane P Wetick Junior Member

    Power MosFet or IGBT

    All the transistors shown on the Heatsink should be replaced as they gave all been overstressed and most likely their usable life has been severely shortened.
    The passive components are most likely OK with the exception of Electrolytic capacitors and diodes...these probably are destroyed. I doubt if a cursory inspection will find all the defective components and a functional test and 48 hour burn-in will be required. A brand new unit is the best compromise here.

    Cheers, DPW [Everything has limitations...and I hate limitations.]
     
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