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Importance of polarity?

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VulcaniaSubmarine Posted messages 558 Status Member -  
VulcaniaSubmarine Posted messages 558 Status Member -
Hello,

I have an excellent quality wireless headset, Sennheiser TR 120 II.

Recently, I moved my furniture, and the headset stopped working. I wondered if it was the power supply, I checked the specifications of the transformer, and I plugged in a universal power supply instead, set appropriately. Nothing worked. But what shocks me is that while we can set this power supply in terms of voltage, there’s no access to the polarity anywhere.

Hence my question: could the disregard for the polarity cause the headset to not work? Is it really important, or not, or just a little? Or is it that the headset is broken (I would be upset, I haven't had it for that long, and I don't use it very often).

I wanted to test the transformer provided with the headset using a multimeter. But I'm not used to using this device, and I'm not sure I handled it correctly, despite the tutorials. According to the multimeter, the power supply was broken, not putting out anything.

I tried with another universal power supply: same result. Nothing, no lights turning on.

So, in your opinion, is my headset finished, or is it just that I can't connect my power supplies correctly?

Thank you for shedding some light on my question... Looking forward to hearing from you.

4 answers

  1.
    jeanbern Posted messages 13740 Registration date   Status Contributor Last intervention   5 136
     
    Hi,
    How many wires do you have? And what color?

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    Thank you
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    1. VulcaniaSubmarine Posted messages 558 Status Member 7
       
      Hi,
      2 wires, one of which has a white stripe. But it's the power supply that's giving me trouble: there's no indication of the polarity on it, and no way to choose it. That's pretty crazy, isn't it? Crappy equipment, if I had known, I would have gotten this from an electronics store.
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    2. VulcaniaSubmarine Posted messages 558 Status Member 7
       
      Can a multimeter be used to determine the polarity of what's coming out of a power supply? In any case, my headset hasn't reacted at all with either of the two power supplies I've tested, both of which seem to be working. It's possible that it’s broken, but I'd be upset about it since I've hardly used it.
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    3. Anonymous user
       
      With a Metrix, no worries about knowing the voltage and polarity!!!
      When the Metrix is set to direct current (symbol = ), the red wire gives the + and the black gives the -, so when you connect it, you know the voltage (indicated by the needle or screen depending on whether it's analog or digital) and you know the polarity (in analog, the needle points left if reversed, in digital there is a + or - indication).
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      1. VulcaniaSubmarine Posted messages 558 Status Member 7 > Anonymous user
         
        Great, thanks, I'm going to test that.
        I can't believe that on a "universal" power supply we can't reverse the polarity. Even the crappiest piece of junk from the far end of Asia does that... I won't be ordering anything from Leroy Merlin anymore, because of that, the unbelievable delivery times, but above all, their shipping fees which are clearly exaggerated. And when we point it out to them, a flood of excuses but not a single gesture of goodwill to make up for it. I'm done with those guys.
        I'm going to see if I can test it with my multimeter (digital readout), but I’m afraid my Sennheiser has let me down. Yet I haven't used it much, and normally it's a good brand, right?
        Thanks again...
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  2. jeanbern Posted messages 13740 Registration date   Status Contributor Last intervention   5 136
     
    Yes, polarity is important.
    If you reverse it, the woofers will pull the diaphragm inward.
    You can test it with a flat battery, for example (except for less than 4.5 volts).

    Thank you.
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  3. Anonymous user
     
    Hello
    Polarity is essential; on certain equipment (most often), an inversion simply leads to the destruction of the device, while for others there is protection, so it is difficult to draw a true conclusion.
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  4. jeanbern Posted messages 13740 Registration date   Status Contributor Last intervention   5 136
     
    Generally, in a power supply, the polarity + (inside)
    and - (outside)

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    Thank you
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    1. VulcaniaSubmarine Posted messages 558 Status Member 7
       
      Yes, I've figured out how it's set up, but what seems crazy to me is that on the universal power supply they sold me, there are no indications of the polarity and even crazier, no way to choose it. Usually, there's a unipolar switch to set the + to the center or to ground, but here, nothing at all. When I think that it's a power supply I ordered from Leroy Merlin, not only did they take forever to deliver it, but they also have exorbitant shipping fees, they're never going to see me again.
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