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Relay Functionality Question

  1. Jan 16, 2012 #1
    Hello all! I just had a quick question to ask about relays. I understand that you can use a relay as an input voltage-controlled on-off switch but it can also be used to control the output voltage to the load controlled by an input voltage, correct? If I am understanding everything correctly, since the pole and throw determines how many terminals there are and the number of terminals represent how many output 'configurations' can exist. So a single-pole single-throw has two terminals (Wiki says 4 terminals total if you include two terminals for the coil... don't really know what that means so for this example I'm going to ignore it :)) therefore the relay can be used as an on off switch whereas a single-pole double-throw switch (3 terminals not including the two terminals for the coil) can have a 0V 'off' output, as well as 2 more set 'on' output values. Is this correct? If so, I guess I kind of answered my own question.

  2. jcsd
  3. Jan 16, 2012 #2
    The output of a relay does not produce electricity. It merely shorts or opens two terminals.
  4. Jan 16, 2012 #3
    Yes, I understand this, the load will have a separate power supply. I was just wondering if the output of the power supply can be controlled with a relay....
  5. Jan 16, 2012 #4
    You have to periodically turn it on and off to do that.
  6. Jan 16, 2012 #5
    From what you've described I don't think a relay will do what you want. There are other devices that will do almost anything you can think of. If you can tell us a little more about your circuit, we'll be better able to help.

    Is your coil voltage AC or DC? What voltage is it?
    Likewise, is the switched voltage AC or DC and what is its voltage?
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