Help - how to test an inverter transformer

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  • matthmal
    Badcaps Veteran
    • Nov 2012
    • 306
    • Malta

    #1

    Help - how to test an inverter transformer

    Hi Guys,

    I have been wondering how could I learn to test Inverter transformers and any other sort of transformers. I have been googling around and tried to understand the below webpage:
    http://www.jestineyong.com/test-lcd-...r-transformer/

    Can anyone please assist and teach me how to test them please?

    Thanks,
    Matt
  • stj
    Great Sage 齊天大聖
    • Dec 2009
    • 30965
    • Albion

    #2
    Re: Help - how to test an inverter transformer

    http://members.ozemail.com.au/~bobpar/fbt.htm
    i use this to test transformers.
    the pdf has the schematics to make one.

    Comment

    • keeney123
      Lauren
      • Sep 2014
      • 2536
      • United States

      #3
      Re: Help - how to test an inverter transformer

      What do you not understand?

      Comment

      • matthmal
        Badcaps Veteran
        • Nov 2012
        • 306
        • Malta

        #4
        Re: Help - how to test an inverter transformer

        Originally posted by stj
        http://members.ozemail.com.au/~bobpar/fbt.htm
        i use this to test transformers.
        the pdf has the schematics to make one.
        Not sure how could i do that.... is the below similar?
        http://www.ebay.co.uk/itm/Philips-Fl...item3f4a76b42b

        Comment

        • matthmal
          Badcaps Veteran
          • Nov 2012
          • 306
          • Malta

          #5
          Re: Help - how to test an inverter transformer

          Originally posted by keeney123
          What do you not understand?
          Can't really understand how to test it and what should be the results.... I understood that an ohm test should take place but i do not know what should the results be and which joints should i test

          Comment

          • stj
            Great Sage 齊天大聖
            • Dec 2009
            • 30965
            • Albion

            #6
            Re: Help - how to test an inverter transformer

            Originally posted by matthmal
            Not sure how could i do that.... is the below similar?
            http://www.ebay.co.uk/itm/Philips-Fl...item3f4a76b42b
            nothing to do with it.

            Comment

            • budm
              Badcaps Legend
              • Feb 2010
              • 40746
              • USA

              #7
              Re: Help - how to test an inverter transformer

              Originally posted by matthmal
              Can't really understand how to test it and what should be the results.... I understood that an ohm test should take place but i do not know what should the results be and which joints should i test
              To do the Ohms test, you will need to get the P/N to find the pinout, you can go to LCDPARTS.NET to see if the transformer you are trying to test is on the site, for example:
              http://lcdparts.net/T.aspx
              Just hit the buy now and the transformer spec will come up.
              http://lcdparts.net/TransformerDetai...ProductID=2732

              You can also remove the transformer to see how the windings are arrange.
              If you have more than one transformer on the board then you can compare the resistance reading. When you work on many of them you will know how the transformer windings are arranged.
              BTW, are you asking about inverter transformer for LCD TV or Flyback transformer for CRT.
              Last edited by budm; 09-14-2015, 11:20 AM.
              Never stop learning
              Basic LCD TV and Monitor troubleshooting guides.
              http://www.badcaps.net/forum/showthr...956#post305956

              Voltage Regulator (LDO) testing:
              http://www.badcaps.net/forum/showthr...999#post300999

              Inverter testing using old CFL:
              http://www.badcaps.net/forum/showthr...er+testing+cfl

              Tear down pictures : Hit the ">" Show Albums and stories" on the left side
              http://s807.photobucket.com/user/budm/library/

              TV Factory reset codes listing:
              http://www.badcaps.net/forum/showthread.php?t=24809

              Comment

              • matthmal
                Badcaps Veteran
                • Nov 2012
                • 306
                • Malta

                #8
                Re: Help - how to test an inverter transformer

                Originally posted by budm
                To do the Ohms test, you will need to get the P/N to find the pinout, you can go to LCDPARTS.NET to see if the transformer you are trying to test is on the site, for example:
                http://lcdparts.net/T.aspx
                Just hit the buy now and the transformer spec will come up.
                http://lcdparts.net/TransformerDetai...ProductID=2732

                You can also remove the transformer to see how the windings are arrange.
                If you have more than one transformer on the board then you can compare the resistance reading. When you work on many of them you will know how the transformer windings are arranged.
                BTW, are you asking about inverter transformer for LCD TV or Flyback transformer for CRT.
                Thanks will try it out and will let you know.

                May I ask you what you think of this:
                http://www.ebay.co.uk/itm/AnaTek-Blu...item2a2ea6e1dd

                I am asking about LCD and any other sort of transformer which you can find in a monitor, tv and electronic devices.

                Comment

                • budm
                  Badcaps Legend
                  • Feb 2010
                  • 40746
                  • USA

                  #9
                  Re: Help - how to test an inverter transformer

                  I never use one of those, I use my SENCORE LC75.
                  http://www.ebay.co.uk/itm/Sencore-LC...item2358eeb120
                  Never stop learning
                  Basic LCD TV and Monitor troubleshooting guides.
                  http://www.badcaps.net/forum/showthr...956#post305956

                  Voltage Regulator (LDO) testing:
                  http://www.badcaps.net/forum/showthr...999#post300999

                  Inverter testing using old CFL:
                  http://www.badcaps.net/forum/showthr...er+testing+cfl

                  Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                  http://s807.photobucket.com/user/budm/library/

                  TV Factory reset codes listing:
                  http://www.badcaps.net/forum/showthread.php?t=24809

                  Comment

                  • matthmal
                    Badcaps Veteran
                    • Nov 2012
                    • 306
                    • Malta

                    #10
                    Re: Help - how to test an inverter transformer

                    Originally posted by budm
                    I never use one of those, I use my SENCORE LC75.
                    http://www.ebay.co.uk/itm/Sencore-LC...item2358eeb120
                    That is surely much better but even more expensive. So the one that i quoted isn't good?

                    Comment

                    • stj
                      Great Sage 齊天大聖
                      • Dec 2009
                      • 30965
                      • Albion

                      #11
                      Re: Help - how to test an inverter transformer

                      each tool has it's own purpose.

                      the blue ringer is just for testing coils / transformers.

                      an LC(R??) meter is also for checking capacitors - it also gives real numbers instead of just a bar of leds.

                      you get what you pay for.

                      Comment

                      • matthmal
                        Badcaps Veteran
                        • Nov 2012
                        • 306
                        • Malta

                        #12
                        Re: Help - how to test an inverter transformer

                        Originally posted by stj
                        each tool has it's own purpose.

                        the blue ringer is just for testing coils / transformers.

                        an LC(R??) meter is also for checking capacitors - it also gives real numbers instead of just a bar of leds.

                        you get what you pay for.
                        May i know which is the secondary and primary windings of an inverter transformer pls? Which is the winding that I am supposed to check?

                        Comment

                        • stj
                          Great Sage 齊天大聖
                          • Dec 2009
                          • 30965
                          • Albion

                          #13
                          Re: Help - how to test an inverter transformer

                          check both.

                          the primary is the one the power goes into and usually looks smaller if you can see it.
                          the secondary is the output to the tube(s)

                          most problems are on the secondary side,
                          but it's worth checking there is no conection between the primary and secondary.

                          Comment

                          • budm
                            Badcaps Legend
                            • Feb 2010
                            • 40746
                            • USA

                            #14
                            Re: Help - how to test an inverter transformer

                            Go here and look at the transformers to see what typical windings for the inverter transformers are (the secondary side high Voltage )winding will use very small wires compared to the primary winding).
                            http://lcdparts.net/T.aspx
                            Click on the 'BUY NOW' button to see the spec and the pinouts.
                            For example:
                            http://lcdparts.net/TransformerDetai...ProductID=2727
                            Never stop learning
                            Basic LCD TV and Monitor troubleshooting guides.
                            http://www.badcaps.net/forum/showthr...956#post305956

                            Voltage Regulator (LDO) testing:
                            http://www.badcaps.net/forum/showthr...999#post300999

                            Inverter testing using old CFL:
                            http://www.badcaps.net/forum/showthr...er+testing+cfl

                            Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                            http://s807.photobucket.com/user/budm/library/

                            TV Factory reset codes listing:
                            http://www.badcaps.net/forum/showthread.php?t=24809

                            Comment

                            • fzabkar
                              Badcaps Veteran
                              • Mar 2009
                              • 772
                              • Australia

                              #15
                              Re: Help - how to test an inverter transformer

                              Originally posted by budm
                              Go here and look at the transformers to see what typical windings for the inverter transformers are (the secondary side high Voltage )winding will use very small wires compared to the primary winding).
                              http://lcdparts.net/T.aspx
                              Click on the 'BUY NOW' button to see the spec and the pinouts.
                              For example:
                              http://lcdparts.net/TransformerDetai...ProductID=2727
                              Thanks for the information.

                              I notice that LCDparts want $22 for the transformer alone, whereas shopjimmy are selling an entire 4H.V0708.321 inverter (which uses 6 of those transformers) for $10.

                              http://www.shopjimmy.com/auo-19-2600...t-inverter.htm

                              Comment

                              • budm
                                Badcaps Legend
                                • Feb 2010
                                • 40746
                                • USA

                                #16
                                Re: Help - how to test an inverter transformer

                                I only use LCDPARTS.NET for ref info only (I used to buy from them because they are close by in S.F), their prices are way too high.
                                Never stop learning
                                Basic LCD TV and Monitor troubleshooting guides.
                                http://www.badcaps.net/forum/showthr...956#post305956

                                Voltage Regulator (LDO) testing:
                                http://www.badcaps.net/forum/showthr...999#post300999

                                Inverter testing using old CFL:
                                http://www.badcaps.net/forum/showthr...er+testing+cfl

                                Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                                http://s807.photobucket.com/user/budm/library/

                                TV Factory reset codes listing:
                                http://www.badcaps.net/forum/showthread.php?t=24809

                                Comment

                                • matthmal
                                  Badcaps Veteran
                                  • Nov 2012
                                  • 306
                                  • Malta

                                  #17
                                  Re: Help - how to test an inverter transformer

                                  Originally posted by budm
                                  Go here and look at the transformers to see what typical windings for the inverter transformers are (the secondary side high Voltage )winding will use very small wires compared to the primary winding).
                                  http://lcdparts.net/T.aspx
                                  Click on the 'BUY NOW' button to see the spec and the pinouts.
                                  For example:
                                  http://lcdparts.net/TransformerDetai...ProductID=2727
                                  Hi,

                                  Thanks for your reply. I can't seem to find the transformers that I want on that website though. Can I do something else please?

                                  Thanks,
                                  Matt

                                  Comment

                                  • budm
                                    Badcaps Legend
                                    • Feb 2010
                                    • 40746
                                    • USA

                                    #18
                                    Re: Help - how to test an inverter transformer

                                    Originally posted by matthmal
                                    Hi,

                                    Thanks for your reply. I can't seem to find the transformers that I want on that website though. Can I do something else please?

                                    Thanks,
                                    Matt
                                    But so far you have not given us any information or the pictures of the transformer you are trying get or test. You gave the link in post 4 for the Flyback transformer for the CRT.
                                    Last edited by budm; 10-05-2015, 02:31 PM.
                                    Never stop learning
                                    Basic LCD TV and Monitor troubleshooting guides.
                                    http://www.badcaps.net/forum/showthr...956#post305956

                                    Voltage Regulator (LDO) testing:
                                    http://www.badcaps.net/forum/showthr...999#post300999

                                    Inverter testing using old CFL:
                                    http://www.badcaps.net/forum/showthr...er+testing+cfl

                                    Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                                    http://s807.photobucket.com/user/budm/library/

                                    TV Factory reset codes listing:
                                    http://www.badcaps.net/forum/showthread.php?t=24809

                                    Comment

                                    • matthmal
                                      Badcaps Veteran
                                      • Nov 2012
                                      • 306
                                      • Malta

                                      #19
                                      Re: Help - how to test an inverter transformer

                                      Originally posted by stj
                                      check both.

                                      the primary is the one the power goes into and usually looks smaller if you can see it.
                                      the secondary is the output to the tube(s)

                                      most problems are on the secondary side,
                                      but it's worth checking there is no conection between the primary and secondary.
                                      Hi,

                                      Thanks for your reply. I came through the attached... is that the way that the windings need to be checked?


                                      Thanks,
                                      Matt
                                      Attached Files

                                      Comment

                                      • budm
                                        Badcaps Legend
                                        • Feb 2010
                                        • 40746
                                        • USA

                                        #20
                                        Re: Help - how to test an inverter transformer

                                        How about the pictures of the top side of the board? and also the whole board both sides.
                                        What is the make and model of this product you are working on? The more information we get the more we can help.
                                        It looks to be correct as you have marked for the High Voltage secondary winding.
                                        Last edited by budm; 10-05-2015, 02:34 PM.
                                        Never stop learning
                                        Basic LCD TV and Monitor troubleshooting guides.
                                        http://www.badcaps.net/forum/showthr...956#post305956

                                        Voltage Regulator (LDO) testing:
                                        http://www.badcaps.net/forum/showthr...999#post300999

                                        Inverter testing using old CFL:
                                        http://www.badcaps.net/forum/showthr...er+testing+cfl

                                        Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                                        http://s807.photobucket.com/user/budm/library/

                                        TV Factory reset codes listing:
                                        http://www.badcaps.net/forum/showthread.php?t=24809

                                        Comment

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