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Centrex CTPVR120TT - bad 400V unit

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    Centrex CTPVR120TT - bad 400V unit

    A few days ago, I bought a Centrex CTPVR120TT.
    When I plugged it in, there was a buzzing sound from the power supply. This was caused by a bulging 400V electrolytic capacitor (which has lost significant capacitance), causing mains hum to be induced into the SMPS transformer.

    All of the "DK" brand electrolytic capacitors were replaced with Nippon Chemi-Con KY series, with the 400V unit being a Nippon Chemi-Con KMG series.
    The electrolytic capacitors were upgraded as below:
    C6: 120uF 400V
    C11 (primary 16V supply), C17 and C18 (33V rail): 100uF 50V
    C8, C9-1: 2200uF 10V (5V rail)
    C7, C10: 1000uF 16V (7.5V rail)
    C14, C15: 2200uF 6.3V (3.3V rail)

    D8 (HER302) was removed with a dual-unit 10A 0.55Vf (approx) Schottky rectifier (e.g. YG802C04R) placed in the D10 position (3.3V rail), along with D2 (HER302) (5V rail) being replaced with a 10A 0.55Vf (approx) Schottky rectifier (e.g. MBRF1045).
    Replacement of these two rectifiers improved the regulation of all of the supply rails.

    Has anyone ever seen "DK" elecytrolytic capacitors before?
    Attached Files
    My first choice in quality Japanese electrolytics is Nippon Chemi-Con, which has been in business since 1931... the quality of electronics is dependent on the quality of the electrolytics.

    #2
    Re: Centrex CTPVR120TT - bad 400V unit

    What was brand/series of mains cap? DK also?

    Toast
    veritas odium parit

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      #3
      Re: Centrex CTPVR120TT - bad 400V unit

      As I said before, all of the electrolytics are DK brand, including the 400V unit.
      My first choice in quality Japanese electrolytics is Nippon Chemi-Con, which has been in business since 1931... the quality of electronics is dependent on the quality of the electrolytics.

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