How to measure a 100/1000BASE-T transformer module ?

Collapse
X
Collapse
+ More Options
Posts
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • Gabriel
    Badcaps Veteran
    • Jan 2010
    • 620
    • Norway
    #1

    How to measure a 100/1000BASE-T transformer module ?

    I have a router that all the lan ports + the wan port is dead.

    How can I test the transformer modules to see if they are working or not ?
    I have the Delta Lf9402 modules.


    Thanks
    Tags: None
    • japlytic
      Badcaps Legend
      • Oct 2005
      • 2086
      • Australia
      #2
      Re: How to measure a 100/1000BASE-T transformer module ?

      Did the WAN port get connected to a phone line? Some people think the "internet" port is for the phone line, and many are not marked to warn people not to connect it to a phone line.
      Ethernet transformers can be a bit hard to test, considering that the windings show as shorted at DC or low frequencies. I found that fact useful in tracking down a defective network port in our new house, and the cause was a wire (used for Gigabit) missing its target on the wallplate connector.
      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.

        Comment

        • Gabriel
          Badcaps Veteran
          • Jan 2010
          • 620
          • Norway
          #3
          Re: How to measure a 100/1000BASE-T transformer module ?

          I found this router in the garbage at work so I do not know what happend to it but it has had a hard life - https://www.badcaps.net/forum/showth...3177#post93177

          I replaced the two blown caps but the lan and wan port was still dead.
          I was up all night and removed and measured all the electrolytic caps but they were all fine. I did notice the ip101a ethernet transceiver was really hot, I will get one on ebay and see if replacing it helps.

            Comment

            Previous template Next

            Related Topics

            Collapse
            • AlexVG
              Replacing the WiFi module on a vacuum cleaner iROBOT i7
              by AlexVG
              Hi,
              I have had an iROBOT i7 with a camera error (error 68) version REV M, year 2018.

              I bought a liquid damaged Mainboard with WiFi module, from the same vacuum cleaner, but a different year and a different version (REV G).
              (This board does not respond, only the LEDs light up in a circle.
              The liquid damage is catastrophic and restoration is impractical).
              (I bought this board to get the WiFi module and camera).

              The boards are completely different in the installation of elements, even the connector for the WiFi module is different.

              If...
              10-22-2024, 07:20 AM
            • repair-it
              TOSHIBA DLP 52HM95 How to reset timer module on bulb
              by repair-it
              I replaced the bulb only on my Toshiba DLP The bulb is a TB-25. This is the first time I've done a bulb only replacement. Supposedly there is a timer module that needs to be re-calibrated or reset. I don't know where the module is located. I see some vendors selling the bulb with the housing stating module included which leads me to think the module is located inside the enclosure the bulb mounts in, but I didn't see it. Maybe it's inside the plug attached to the bulb?

              Anyway - I am seeking information on how to reset this so called module so that the lamp will operate. Apparently...
              10-11-2023, 07:18 PM
            • mikey5791
              Is it possible for transformer substitution?
              by mikey5791
              Hi all,
              Got this local made DC power supply (12/14V) given free as the transformer has melted. There is no marking or indication to identify what type or rating of transformer used.
              Fyi,. I had a busted autogate mainboard with transformer with marking 13-0-13 . Is this the 13v dc type transformer?
              My questions are
              1. How do i test to see if the transformer is in good working condition?
              2. Can this transformer (marking 13-0-13) be used to replace the melted transformer on the DC power supply?
              Hope you guys understand what i was asking. My intention is...
              11-03-2022, 02:11 AM
            • m1ch43lzm
              70mai Dash Cam A510 - help identifying connector on camera module
              by m1ch43lzm
              Hi everyone
              I have a 70mai Dash Cam A510 which failed after about 3 months of being installed in my car, likely due to heat, i got it from aliexpress so no point in trying to return it for warranty (and shipping it back would cost me almost the same as a new one from ali)
              The camera would boot loop showing 70mai logo on the screen, sometimes it would boot fine then the live view would freeze or display purple lines

              I already took it apart, and found out that the camera boots fine if i unplug the camera module from the main PCB, sometimes "playing" with the connector...
              05-11-2025, 06:02 PM
            • dennis_elx33
              3PHASE STEP-DOWN Transformer in Check
              by dennis_elx33
              Hello All,

              i would like to post an interesting topic regarding 3-phase stepdown transformer which we suspect to cause an overcurrent (138A) which resulted to power tripped off of the HV power supply (80KV output).


              Problem statement: Power tripped Off

              Initial Problem: Found 2 IGBT and 2 rectifier diodes shorted (burnt).

              Action Done:
              1) Replaced the faulty parts with good spare.
              2) Measured impedance of the 3phase input lines and found that L2 to L3 has 23.3ohm while other pairs are 51Kohm. This pins will...
              12-02-2024, 06:52 AM
            • Loading...
            • No more items.
            Working...