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Thread: Speedrite Electric Fence

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    Default Speedrite Electric Fence

    Hi all,
    I'm trying to fix a Speedrite 8000 electric fence unit. LED2 right side on DC side not flashing. Fuse OK,

    The four diodes are not in a bridge rectifier config rather 2 in parallel then 2 in parallel with cathodes of 1st pair connected to anodes of 2nd pair.
    Don't know what the 2 large red components top right are or the 2 blue at left of middle.
    I assume silver mounted horizontal top middle is an electrolytic cap?
    Most of stuff on AC side have porcalain beads protecting legs.

    I'm trying to understand AC to DC path before I start removing live testing. Any help appreciated.


    regards
    Neil



    Last edited by ngr; 27-01-20 at 02:30 PM.



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    Big blue thing looks like a Riva capacitor, also appears to be the capacitive dropper to feed electronics ; check it

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    Ok. AC in via Large blue cap, on left, then through green wirewound resistor (Burnt check) through two more resistors to a zener diode. The large electro is then across this to create the DC rail.
    First test. Is there any DC Voltage across that electro ?
    The Varisistor (V1) after the wirewound resistor may be shorted.

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    remember to listen you can hear the oscillator if its working . the two resisters after the wire wound go high so you may not have sufficient rail volts . yes the v1 is most likely shorted as well

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    Thanks for your replies, finally had a chance to get back to it.
    DC across large metallic cap and large diode, need to test SCR2 (if it is).




    Couldn't find anything exactly on it, Is it a SCR? Was covered in shellac, possible replacement part if faulty?
    What is is purpose here?.
    thanks in advance.

    neil

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    Looks like the SCR with heat sink is crook.

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    That's a bt151-800r thyristor (SCR) ...cheap as chips ...

    The condition of the output transformer (and other components) should be checked before replacing with new one and blithe-fully turning the power on

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    Thanks, the TYM825 with the heat sink is shorted between A & C and $2 at RS, but I have to buy a tube of 50, I'll have 49 spares

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    I thought smallest SSM was 5 units... oh well, depends where you are I guess =)

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    The scr wont be the final fault

  • The Following User Says Thank You to hinekadon For This Useful Post:

    wotnot (02-02-20)

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    Quote Originally Posted by hinekadon View Post
    The scr wont be the final fault
    That is for sure.

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    Quote Originally Posted by ngr View Post
    Thanks, the TYM825 with the heat sink is shorted between A & C and $2 at RS, but I have to buy a tube of 50, I'll have 49 spares
    If it's a BT151-800r ( I haven't checked) and you're in Australia...

    For smaller quantities see

    5 for $1.15 each = $5.75 total (+ postage).

    Also

    $1.14 for quantity 1.

    All plus GST of course.

    ...and there are many other suppliers.

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    hinekadon (03-02-20)

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    Finally got back to it.
    Hinekadon was right, the 4 large diodes were crook as well (shorted). Replaced them and all good.
    Thanks everyone.
    Interestingly i thought things would go open, not here the higher currents may have something to do with it?

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    hinekadon (15-02-20)

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