Announcement

Collapse
No announcement yet.

Identifying electronic component

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    Identifying electronic component

    Hello experts,

    do you have any idea what are the components labeled with letter V on PCB?

    I cannot measure resistance with the multimeter (it's probably very high). There is a picture in the attachment. These elements have some kind of protective function. One side is connected to the ground.


    Thank you in advance.
    Attached Files

    #2
    Re: Identifying electronic component

    they are probably some form of zener diode

    Comment


      #3
      Re: Identifying electronic component

      Can you post a large picture of the component? 455x134 is too small to make out the logo. is it C? 9CA I suspect they are tvs components
      Last edited by R_J; 11-12-2020, 11:03 AM.

      Comment


        #4
        Re: Identifying electronic component

        Thanks for the feedback.
        This is the best picture I can do, because the components are tiny.
        It is written CM 9CA and the logo is very much like Toyota.
        This is the analog input card of the PLC (receives thermocouples). These are the first elements that have connection to the thermocouple in the field. When there is an overvoltage they usually go short to the ground.
        Attached Files

        Comment


          #5
          Re: Identifying electronic component

          bi-directional TVS diode - probably 9v

          Comment


            #6
            Re: Identifying electronic component

            Originally posted by stj View Post
            bi-directional TVS diode - probably 9v
            My thinking, too. The logo looks like that of General Semiconductor (a division of Vishay).
            Last edited by PeteS in CA; 11-13-2020, 12:58 PM.
            PeteS in CA

            Power Supplies should be boring: No loud noises, no bright flashes, and no bad smells.
            ****************************
            To kill personal responsibility, initiative or success, punish it by taxing it. To encourage irresponsibility, improvidence, dependence and failure, reward it by subsidizing it.
            ****************************

            Comment


              #7
              Re: Identifying electronic component

              I think they are Vishay bi-directional Transzorb SMBJ33A (CM) I suspect the 9CA could be date/mfg code
              The ones marked MM are directional type. Here is the same part with a different date code
              Attached Files
              Last edited by R_J; 11-13-2020, 06:18 PM.

              Comment


                #8
                Re: Identifying electronic component

                Thank you very much for the information. I couldn't test it with multimeter set to test diodes and therefore I was confused. Now, from the datasheet I can see that the applied voltage must be higher in order the diode to start conducting.
                Last edited by Askic; 11-15-2020, 02:49 AM.

                Comment


                  #9
                  Re: Identifying electronic component

                  that's how it works, when the voltage rises above the level safe for the circuit, the diode turns on and shorts the voltage to ground.

                  Comment


                    #10
                    Re: Identifying electronic component

                    Hello guys,

                    can you please help me identify components show in the attached picture?
                    I have found that component nr. 1 is tantalum capacitor, most likely 33 uF, 16V
                    https://cdn.badcaps-static.com/pdfs/...88116449c7.pdf from manufacturer Vishay.
                    However, I'm not sure what components 2 and 3 are. They are most likely produced by Vishay and they some kind of Zener or TVS diodes, but I'm not sure if this 25A means 25 amperes. It sound a lot to me.
                    I hope you'll be able to help me.

                    Thank you very much.
                    Attached Files

                    Comment


                      #11
                      Re: Identifying electronic component

                      Yes, they are TVS diodes.
                      Attached Files

                      Comment


                        #12
                        Re: Identifying electronic component

                        Originally posted by diif View Post
                        Yes, they are TVS diodes.
                        Thank you!

                        Comment

                        Working...
                        X