584,830 active members*
5,599 visitors online*
Register for free
Login
Results 1 to 5 of 5
  1. #1
    Join Date
    Sep 2009
    Posts
    277

    Repair and upgrade of high voltage power supply

    Hey guys

    If a 50w power supply needs a new flyback can a higher rated one be installed I.e. add a 100w rated flyback in place of the old 50w one? Also upgrade the rectified to a higher rated one. I.e remover the 1A one and add a 3+ amp one.

    Sent from my SM-N960F using Tapatalk

  2. #2
    Join Date
    May 2013
    Posts
    480

    Re: Repair and upgrade of high voltage power supply

    did you burn out the 50 watt transformer?


    if you can verify the 100 watt flyback has the same turns ratio, you may be able to change the air gap of the core so that they both have the same inductance. but if the 50 watt is burned out then you can't measure its inductance.

    it would take some signficant reverse engineering to subsitute a different transformer into a flyback converter, it may not be worth your time to do so. you risk messing up the control loop of the power supply as well as burning out the switch (which is likely a 500 +volt mosfet but it could be a 500-900 volt transistor or a high voltage igbt)

    the flyback control loop in your case probably works by waiting until the current exceeds a given value and then it turns off the switch. subsituting a larger transformer (which may have much lower inductance) will require a higher current capacity in the switch, and in order to make it work you may have to change the current sense resistor for a lower value.

  3. #3
    Join Date
    Sep 2009
    Posts
    277

    Re: Repair and upgrade of high voltage power supply

    Quote Originally Posted by Eldon_Joh View Post
    did you burn out the 50 watt transformer?


    if you can verify the 100 watt flyback has the same turns ratio, you may be able to change the air gap of the core so that they both have the same inductance. but if the 50 watt is burned out then you can't measure its inductance.

    it would take some signficant reverse engineering to subsitute a different transformer into a flyback converter, it may not be worth your time to do so. you risk messing up the control loop of the power supply as well as burning out the switch (which is likely a 500 +volt mosfet but it could be a 500-900 volt transistor or a high voltage igbt)

    the flyback control loop in your case probably works by waiting until the current exceeds a given value and then it turns off the switch. subsituting a larger transformer (which may have much lower inductance) will require a higher current capacity in the switch, and in order to make it work you may have to change the current sense resistor for a lower value.
    Ah ok I hear what you are saying. No not burned out but may want to upgrade the tube at a later stage and with exchange of $1 to R15, $100 is R1500 so I'm thinking to upgrade rather then buy new. BUT if it's not worth it then I'll have to buy a new one when the time comes

    Sent from my SM-N960F using Tapatalk

  4. #4
    Join Date
    May 2013
    Posts
    480

    Re: Repair and upgrade of high voltage power supply

    i'm not sure its worth your time or money to attempt to drive a 100w tube from a 50 watt power supply.

  5. #5
    Join Date
    Sep 2009
    Posts
    277

    Re: Repair and upgrade of high voltage power supply

    Yeah inguess bit the bullet and buy the ps as well.
    Thanks for your assistance

    Sent from my SM-N960F using Tapatalk

Similar Threads

  1. High voltage power supply, low voltage perihperals
    By feechl in forum CNC Machine Related Electronics
    Replies: 2
    Last Post: 01-07-2014, 02:12 AM
  2. Power supply step down? Gecko high voltage?
    By bead in forum CNC Machine Related Electronics
    Replies: 8
    Last Post: 07-06-2010, 04:03 AM
  3. Low(ish) voltage high amp power supply?
    By DeusExMachina in forum CNC Machine Related Electronics
    Replies: 2
    Last Post: 05-23-2009, 03:56 AM
  4. High voltage & high power servo drive design
    By Xerxes in forum CNC (Mill / Lathe) Control Software (NC)
    Replies: 32
    Last Post: 08-23-2008, 03:24 AM
  5. Power supply voltage too high
    By spoiledbrat in forum CNC Machine Related Electronics
    Replies: 8
    Last Post: 06-14-2005, 03:39 AM

Tags for this Thread

Posting Permissions

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