Page 1 of 2 12 LastLast
Results 1 to 10 of 16

Thread: Keep losing LOC Ideas?

  1. #1
    Join Date
    Apr 2010
    Location
    Grand Rapids, Mi
    Posts
    2,495

    Default Keep losing LOC Ideas?

    I have lost 3 LOC diodes in the past week, the replacements haven't lasted but about an hour each. There are three in series, all have LASORBs, it is always the first in the series to fail. I am using a 17v 4amp laptop supply and a flexmod.

    Any ideas seems so weird out of nowhere it is making them into LEDs.

    Thanks
    leading in trailing technology

  2. #2
    Join Date
    Jun 2010
    Location
    Australia
    Posts
    3,730

    Default

    Being series wired, and the 1st goes each time, check for ground faults with your isolation on that particular diode housing.

    This is why I decided to wire mine in parallel with resistors to share current...
    This space for rent.

  3. #3
    Join Date
    Apr 2010
    Location
    Grand Rapids, Mi
    Posts
    2,495

    Default

    Quote Originally Posted by dnar View Post
    Being series wired, and the 1st goes each time, check for ground faults with your isolation on that particular diode housing.

    This is why I decided to wire mine in parallel with resistors to share current...
    I did even swap mounts and both are isolated on a meter. Also swapped Len's so I don;t think it is a reflection issue.
    leading in trailing technology

  4. #4
    Join Date
    Jun 2010
    Location
    Australia
    Posts
    3,730

    Default

    Quote Originally Posted by polishedball View Post
    I did even swap mounts and both are isolated on a meter. Also swapped Len's so I don;t think it is a reflection issue.
    Try soak testing without lens and the housing removed for a while, then add lens, then remount.
    This space for rent.

  5. #5
    Join Date
    Apr 2010
    Location
    Grand Rapids, Mi
    Posts
    2,495

    Default

    Quote Originally Posted by dnar View Post
    Try soak testing without lens and the housing removed for a while, then add lens, then remount.
    soak test? don;t know what that is.

    I am leaning towards a reflection back into it from the pbs as the cause.
    leading in trailing technology

  6. #6
    mixedgas's Avatar
    mixedgas is offline Creaky Old Award Winning Bastard Technologist
    Infinitus Excellentia Ion Laser Dominatus
    Join Date
    May 2007
    Location
    A lab with some dripping water on the floor.
    Posts
    9,572

    Default

    Quote Originally Posted by polishedball View Post
    soak test? don;t know what that is.

    I am leaning towards a reflection back into it from the pbs as the cause.
    Soak test is "engineerspeak" for run it well cooled, protected from dust, and safe at progressive power levels for long periods of time

    Steve

  7. #7
    Join Date
    Jun 2010
    Location
    Australia
    Posts
    3,730

    Default

    Quote Originally Posted by mixedgas View Post
    Soak test is "engineerspeak" for run it well cooled, protected from dust, and safe at progressive power levels for long periods of time

    Steve
    Correct, as apposed to testing it in a bucket of water!!!
    This space for rent.

  8. #8
    Join Date
    Apr 2010
    Location
    Grand Rapids, Mi
    Posts
    2,495

    Default

    Pretty sure Drlava and Heroic solved my issue last night. Somehow it is assumed there was a resonance in the circuit, added damping resistor and a cap across first diode been fine since.
    leading in trailing technology

  9. #9
    Join Date
    Jun 2010
    Location
    Australia
    Posts
    3,730

    Default

    Interesting.

    How have you wired to C/R, in series (Zobel network) or parallel?
    This space for rent.

  10. #10
    Join Date
    Aug 2009
    Location
    Auburn, Washington
    Posts
    824

    Default

    Quote Originally Posted by polishedball View Post
    Pretty sure Drlava and Heroic solved my issue last night. Somehow it is assumed there was a resonance in the circuit, added damping resistor and a cap across first diode been fine since.
    Can you explain in a little more detail how you solved the problem? Maybe this is why we keep killing 445's when using Flexmods?

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •