Connect with us

Need help desiging "kick start" for a fan

Discussion in 'General Electronics Discussion' started by xReM1x, Jul 28, 2014.

Scroll to continue with content
  1. xReM1x

    xReM1x

    8
    0
    Jul 28, 2014
    hey y'all. I (unfortunately) bought pwm controller from eBay and there is no schematic on the intrent, And I wanna add to this controller a "kick start"
    kick start : http://www.overclockers.com/forums/s...&postcount=822
    http://www.overclockers.com/forums/s...postcount=1214
    So, I dont have schematics or anythingfor the contoller I bought so I need a circuit Separate from the controller, a circuit I could add Additionally to the pwm controller.
    I might could try to make the schematics just by looking at the connections..
    I use fan model PFC1212DE. it draw 4.80A at the start.
    --
    They made it so You have to desolder the inputs to see the mosfets \ transistors..
    expect the mosfets or transistors there are :
    IN5 something big schottky diode.
    555NE timer
    Zener Diode
    2 470uF electrolytic capacitors
    2 non polrazied small capaictors in series.
    1 non polrazied small capaictor
    couple of resistors and potentiometer.
    [​IMG]
    [​IMG]
    --
    [​IMG]
    [​IMG]
    Btw, in the input its not actually a transistor its a voltage regulator, probaly 7812.
     
  2. KrisBlueNZ

    KrisBlueNZ Sadly passed away in 2015

    8,393
    1,271
    Nov 28, 2011
    You could try connecting this circuit onto your PWM controller. It pulls pins 2 and 6 of the 555 low for a short time after power-up, forcing pin 3 high and turning the transistor ON steadily for a short time. Increase the capacitor value for a longer kick-start time.

    269583.001.GIF
     
  3. xReM1x

    xReM1x

    8
    0
    Jul 28, 2014
    And Wire the fan to the output - and +? nothing diffrent? just add this circuit?
    For the resistor, 1W is ok?
     
    Last edited: Jul 29, 2014
  4. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    25,491
    2,833
    Jan 21, 2010
    Keep the fan connected as it is now.

    The 33k resistor only needs to be a 4mW resistor, so even a 1/4W resistor is 60 times as large as it needs to be. A 1W resistor would be fine, but if you have something smaller it would be fine.
     
    KrisBlueNZ likes this.
  5. xReM1x

    xReM1x

    8
    0
    Jul 28, 2014
    ok, I will buy the compontes build it on a breadbored and see if it will work, thanks for helping me. :)
     
  6. xReM1x

    xReM1x

    8
    0
    Jul 28, 2014
    Update : I bought and built it on a breadboard, It doesnt work, the capacitor get charged to around 9V (I put 12V into the controller is it supposd to be 9V?) but doesnt discharge, And I can control the speed of the fan with the potentiometer but not 0-100% I can controller it around 70%-100% And it was not like that before..
     
  7. xReM1x

    xReM1x

    8
    0
    Jul 28, 2014
    Any one?
     
  8. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    25,491
    2,833
    Jan 21, 2010
    It sounds to me like you may have the transistor around the wrong way. The cap should charge to 12v, and yeah, it shouldn't discharge in operation. 9V is suspiciously like the base emitter breakdown voltage to me.
     
  9. xReM1x

    xReM1x

    8
    0
    Jul 28, 2014
    [​IMG]
    like here?
     
  10. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    25,491
    2,833
    Jan 21, 2010
    Looks right.

    If you disconnect the base of the transistor from the circuit, does the capacitor charge up to 12V, and do you have full control once more?
     
  11. xReM1x

    xReM1x

    8
    0
    Jul 28, 2014
    If I disconnect the base of the transistor from the circuit, the capacitor chrage up again to 9V And I dont have full control.
    But I I found out that 2 of the wire that connect to to the 555 were touching each other (I just soldered some wires from the breadboard I still didnt soldered it on a board correctly.)
     
  12. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    25,491
    2,833
    Jan 21, 2010
    If its not working now you've corrected the short, then you have a wiring error because with the transistor not connected to the resistor/diode/cap, the capacitor should charge up to the full supply voltage (12V).

    Also with the base disconnected, the transistor should do nothing to your circuit.

    Remove the transistor completely to verify that it's the transistor that's causing the problem. If your problems persist, it's not the additional circuitry.
     
  13. xReM1x

    xReM1x

    8
    0
    Jul 28, 2014
    Yep, I fixed it all, but now there is something else.. (arr..)
    I think the controller is fucked, I disconnected all the wiring and it still doesnt regulate 100%.
    and now kick start.
    :\
    I think I should just build a new pwm controller without wasting time using those crappy made in china controllers.
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-