about transformer

Discussion in 'General Electronics Chat' started by hassi, Mar 1, 2013.

  1. hassi

    Thread Starter New Member

    Mar 1, 2013
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    why multimeter not beep on connecting its probes with wires of primary side of step down transformer?
     
    Last edited: Mar 1, 2013
  2. williejon

    New Member

    Feb 18, 2013
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    Read the instructions again. The acoustic "beep" is usually a warning for low power or wrong range. Check the manual for how and why you are being signaled. Some meters are letting you know they need protection.
     
  3. hassi

    Thread Starter New Member

    Mar 1, 2013
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    it means if step down transformer then on connecting multimeter will not beep?
     
  4. #12

    Expert

    Nov 30, 2010
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    It means, "Read the instructions for your meter". We can not read it from here.
     
  5. ScottWang

    Moderator

    Aug 23, 2012
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    Yeah,Read the instructions.

    And talking about what range are you measuring? (V,R,Diode,etc...)

    And shows a photo of your transformer and the infos about the tranformer.
     
  6. williejon

    New Member

    Feb 18, 2013
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    What function select are you on? Before talking about "step down" or troubleshooting, you need to understand the "beep." It could very well be that the sensor is telling you that, though you have continuity, you have gone below a threshhold for "standard line voltage" precisely because you are on the secondary. I am not trying to be a wise guy. I am just suggesting that you need to tell us what function you are on and what the "beep" means without bringing the transformer into it.
     
  7. BillB3857

    Senior Member

    Feb 28, 2009
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    If you are measuring the resistance of the primary, it is probable that the resistance is higher than the limit used by your meter to test continuity.
     
  8. hassi

    Thread Starter New Member

    Mar 1, 2013
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    i m checking conductivity of both sides. then i have seen that on primary side it'll not beep bt on secondary side it beep. so why there is negligible resistsnce or current flowing on secondary side even no supply is given to transformer.......?
    and why there is infinite resistance on primary side?
     
  9. #12

    Expert

    Nov 30, 2010
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    The resistance of the primary is not infinite. It is merely outside the range of you meter.
    Why is the resistance of the secondary winding negligible? Because it is built for high current and low voltage. You need fat wires to carry a lot of current.
     
  10. hassi

    Thread Starter New Member

    Mar 1, 2013
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    i don't get satisfactory answer. so pls help me to get right answer.
    how can resistance on primary side be out of range?
    i'll happen only in two case:
    1- if on primary side resistance is too less i.e. say below 50Ω.
    2- or if resistance is too much i.e. say beyond mega ohm....

    now i culdn't think about 2nd case.
    if 1 case is valid then multimeter should show conductivitymeans it shouls beep.........
    :(
    now tell me something.......
     
  11. hassi

    Thread Starter New Member

    Mar 1, 2013
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    pls help to get the right ans of this ques......
     
  12. #12

    Expert

    Nov 30, 2010
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    Read the instructions for your meter to find out what the range is on the conductivity scale.

    Conductivity range usually sends .001 amp through the device under test. The display shows the voltage at which the device conducts .001 amp, and that range is usually 1 volt maximum. If the resistance you are measuring is more than 1000 ohms, it will be out of range. It does not have to be millions of ohms to be out of range of your meter. Read the instructions to find out what YOUR meter does.
     
  13. BillB3857

    Senior Member

    Feb 28, 2009
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    Can you tell us the actual resistance of the primary in ohms? It could also be that you actually have a bad transformer with an open winding in the primary.
     
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  14. hassi

    Thread Starter New Member

    Mar 1, 2013
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    as there is only reactance of coil bt not resistance , so on checking conductivity it shows no resistance. bt it should be happen on both sides which is not happening in actual. so why it is so?
    nd one more thing there is no fault in transformer.......
     
  15. shortbus

    AAC Fanatic!

    Sep 30, 2009
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    Maybe your primary is useable on two voltages, like 110/220 volts. And you are measuring one wire from one coil and other wire from other coil without the two coils wired together?
     
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  16. kubeek

    AAC Fanatic!

    Sep 20, 2005
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    There surely IS some resistance on both the primary and the secondary. Nothing in this world except for superconductors has zero resistance.
    Second thing, have you finally read the manual to your meter? For example my meter in continuity test mode beeps only when the resistance between leads is <100Ω, and the primary will likely be more.
     
    #12 likes this.
  17. shortbus

    AAC Fanatic!

    Sep 30, 2009
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    Manuals? We don't need no stinkin' manuals! :)
     
  18. BillB3857

    Senior Member

    Feb 28, 2009
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    Manuals are only inserted with equipment to cover any liability. Manufacturers know we don't read them.
     
  19. williejon

    New Member

    Feb 18, 2013
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    Glad to hear the transformer is good! Here are some statements you have made

    1) the meter "beeps" on the primary
    2) if < 50 ohm or > 100 meg, then NO beep.
    3) the meter is in range
    -----
    4) the meter beeps on the primary and is in range(from #1 and #2)
    -----
    5) the meter does NOT beep on the secondary
    6) the meter SHOULD beep on the secondary
    7) the transformer is GOOD

    Why doesn't the meter beep on the secondary?
    The meter is in range and the transformer is good.

    Maybe the meter isn't working correctly or possibly #6 or #7 is false. #6 is tied partly to the correct working of the meter.
     
  20. hassi

    Thread Starter New Member

    Mar 1, 2013
    18
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    actually u are not getting my point....... firstly tell me something....
    1> can we say that due to only prescense of inductance on secondary side there is no
    power dissipation. so on checking its conductivity multimeter beeps?
    2> if ans of 1> is YES THEN same is on primary side or not?
    3> now u(williejon) are saying that if resistance is <50ohm then it wiil not beep BUT on secondary side i had seen that resistance is near about 5ohm and it also beep.......
    so now pls ans.......
    and pls don't discuss about range becoz i don't think so that it may be reason of my question.........
    plz don't mind. if it is the then pls tell me with correct explanation.......
     
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