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Very low voltage AC Mains supply damage TV

  1. Jun 23, 2015 #1
    my electric supply company some time supply very low voltage which cause damage/burn out my Tv three time
    do you know any sort of device which disconnect power supply to my Tv and my Tv un harm from low voltage my electric company uses 220 volt supply or british system.

    please help me
  2. jcsd
  3. Jun 23, 2015 #2
    If "Voltages fluctuations" is the actual problem that you are facing, then it is better to go with a "Stabilizer" or voltage stabilizer is what actually you call.
  4. Jun 23, 2015 #3


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    The simple solution is to buy a relay that - when activated by hand - can just keep the contacts closed if the voltage is above say 210V.

    Something like this:
    Just adjust the value of the capacitor C so that the relay will be released by too low voltage.
    You must "restart" the system by pressing down the contact by hand. You can buy some button as for this, to keep up safety.
  5. Jun 23, 2015 #4


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    A UPS will do this as well. Plus you get to keep watching TV when the power goes wobbly.

  6. Jun 23, 2015 #5


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    You can buy a "plug in and go" protection relay for under/overvoltage protection:


    It's called a sequence relay which I think means that the relay will disconnect at say 210V and will reconnect automatically when the votage has reached 220V again ( stable for 3 minutes )?
    Last edited: Jun 23, 2015
  7. Jun 26, 2015 #6
    dear Hesch,
    do you know the actual name of this device or it is simply i ask to shop keeper to provide me under/over voltage relay protection switch please kindly tell me
    thank you
  8. Jun 26, 2015 #7


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    I think that the model in #5 is for 600V as the reference voltage, but of course they have other models for 115V and 220V as well ( factory tuned ).
    In the link in #5 there are buttons/links like "where to buy", "questions" and so on.
    Alternative you can consult an electrician. Maybe he has a relay in stock, that fits your voltage ( 220V ), or he can provide one.

    The suggestion in #5 was just an example, there are a lot of undervoltage protection relays, some are more expensive ( with display and everything ), some are cheaper, as the one I suggested ( I think ).

    To find alternatives, you can start here: https://www.google.dk/search?q=unde...-8&oe=utf-8&gws_rd=cr&ei=DiuNVeqLIYT7UKuwgaAP

    The electrician can easily make some box, wherein to mount the relay, so that the installation will be safe and keeps to law.
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