Announcement

Collapse
No announcement yet.

Samsung LE27T51B inverter problem

Collapse
X
Collapse
 
  • Page of 2
  • Filter
  • Time
  • Show
Clear All
new posts
Previous 1 2 template Next
    #1

    Samsung LE27T51B inverter problem

    Hello!
    Samsung LE27T51B, the inverter tries to start, a short noise sound is heard, but no backlight comes on. Please see attached picture.
    Is there any usual failures on those? Bad transformers?
    There are a bunch of SMD fuses, they're OK.
    The inverter does recieve +24V and ON-signal.
    Could anyone tell the resistance readings on the transformers.
    The transformers have marking "4006A533 008"
    Thanks in advance!
    Attached Files
    Last edited by PowerAmpFreak; 01-31-2013, 11:22 AM.
    Tags: None
    #2
    Re: Samsung LE27T51B inverter problem

    Testing across the bulb connectors directly can sometimes work.
    Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
    For service manual, schematic, boardview (board view), datasheet, cad - use our search.

    Comment

      #3
      Re: Samsung LE27T51B inverter problem

      I get different readings across the bulb connections.
      1. 12k
      2. 1k8
      3. 21k (?)
      4. 1k8
      5. open circuit (?)
      6. 1k8
      7. 12k

      Obviously there are two strange readings. So perhaps those two transformers are bad.
      Will it be worth a try to change transformers or better find a new board?

      Comment

        #4
        Re: Samsung LE27T51B inverter problem

        Pin diagram, incl primary/secondary windings.
        http://www.lcdparts.net/TransformerD...ProductID=2740
        Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
        For service manual, schematic, boardview (board view), datasheet, cad - use our search.

        Comment

          #5
          Re: Samsung LE27T51B inverter problem

          Great! Thanks tom!

          Comment

            #6
            Re: Samsung LE27T51B inverter problem

            Does it have one of these black fuse (F5)?
            Attached Files
            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

              #7
              Re: Samsung LE27T51B inverter problem

              Originally posted by budm View Post
              Does it have one of these black fuse (F5)?
              No, it appears to have only white SMD fuses. But they're all OK.

              Comment

                #8
                Re: Samsung LE27T51B inverter problem

                Today measured the winding resistances of all the 7 inverter transformers.
                One of the them has one winding open circuit.
                Is it normal that one failed transformer will shut down the entire inverter?
                I assume all transformers with its associated drive electronics has fault detection and will disable all inverter action, correct?

                This boils down to the decision of either replace the faulty transformer or replace the entire board.
                But I think I'll go for the transformer change.

                Comment

                  #9
                  Re: Samsung LE27T51B inverter problem

                  Yes, one transformer failed will shut down the inverter. The fault detection works on any bulb open, or any over-currrent of the bulbs.
                  Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
                  For service manual, schematic, boardview (board view), datasheet, cad - use our search.

                  Comment

                    #10
                    Re: Samsung LE27T51B inverter problem

                    Originally posted by PowerAmpFreak View Post
                    But I think I'll go for the transformer change.
                    I repaired a TV with the same bad 4006A transformer. I bought mine from

                    http://www.ebay.com/itm/150706796810

                    $5.50 + free shipping.
                    --- begin sig file ---

                    If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                    We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                    Please do not post inline and offsite as they slow down the loading of pages.

                    --- end sig file ---

                    Comment

                      #11
                      Re: Samsung LE27T51B inverter problem

                      They look like typical DARFON transformers. Glad you found the cause of the problem.
                      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

                        #12
                        Re: Samsung LE27T51B inverter problem

                        Great guys, I'll go for the transformer change. Thanks!

                        Comment

                          #13
                          Re: Samsung LE27T51B inverter problem

                          Usually if I found there is " two second to black screeb". I will displace the inverter board directly. Please let me know your outcome when you have replace the transformer.
                          It seems it should more cheaper to replace the broken than the entire inverter board.

                          Thanks

                          Comment

                            #14
                            Re: Samsung LE27T51B inverter problem

                            Originally posted by eklunge View Post
                            Usually if I found there is " two second to black screeb". I will displace the inverter board directly. Please let me know your outcome when you have replace the transformer.
                            It seems it should more cheaper to replace the broken than the entire inverter board.

                            Thanks
                            Yes, I will replace the transformer in a few days and gladly tell the outcome!

                            Comment

                              #15
                              Re: Samsung LE27T51B inverter problem

                              One inverter transformer replaced and set is back to operation!

                              Comment

                                #16
                                Re: Samsung LE27T51B inverter problem

                                Nice one.
                                Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
                                For service manual, schematic, boardview (board view), datasheet, cad - use our search.

                                Comment

                                  #17
                                  Re: Samsung LE27T51B inverter problem

                                  Originally posted by PowerAmpFreak View Post
                                  One inverter transformer replaced and set is back to operation!
                                  Wow, you got an inverter transformer from China in less than 5 days?
                                  --- begin sig file ---

                                  If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                                  We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                                  Please do not post inline and offsite as they slow down the loading of pages.

                                  --- end sig file ---

                                  Comment

                                    #18
                                    Re: Samsung LE27T51B inverter problem

                                    Good job. Can you tell me where to buy the inverter yransformer. Thanks

                                    Comment

                                      #19
                                      Re: Samsung LE27T51B inverter problem

                                      Originally posted by eklunge View Post
                                      Good job. Can you tell me where to buy the inverter yransformer. Thanks
                                      Seriously?

                                      Did you read Post #10???
                                      --- begin sig file ---

                                      If you are new to this forum, we can help a lot more if you please post clear focused pictures (max resolution 2000x2000 and 2MB) of your boards using the manage attachments button so they are hosted here. Information and picture clarity compositions should look like this post.

                                      We respectfully ask that you make some time and effort to read some of the guides available for basic troubleshooting. After you have read through them, then ask clarification questions or report your findings.

                                      Please do not post inline and offsite as they slow down the loading of pages.

                                      --- end sig file ---

                                      Comment

                                        #20
                                        Re: Samsung LE27T51B inverter problem

                                        Originally posted by retiredcaps View Post
                                        Wow, you got an inverter transformer from China in less than 5 days?
                                        Not from China, but from a local component supplier!

                                        Comment

                                        Previous 1 2 template Next
                                        Working...
                                        X