Switch with three positions

Discussion in 'General Electronics Chat' started by Vindhyachal Takniki, Feb 17, 2016.

  1. Vindhyachal Takniki

    Thread Starter Member

    Nov 3, 2014
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    1. I have to search for switch which has three positions: off, medium, high. Voltage is 220Vac & current is around 400mA.
    Off means no connection to load, medium means connection to load via a diode in series & 220v ac main(half wave), & high means entire main connection to load.
    2. I have found a switch from local market as in attached pdf. But it has four positions. It has total 10 pins on it. 5 on each side.
    There is one common connection on each side, which make connection with other 4 terminals, as switch is toggled.
    3. What do these switches called, are these Dual pole 4 throw?? I am looking for three position switch. i dont know what name to search for these switches? I need this kind of switch whose handle is on top as in attached pdf.
     
  2. AnalogKid

    Distinguished Member

    Aug 1, 2013
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    Does the off position have to be at one end, or can you use a center-off toggle switch? The positions would be medium - off - high.

    ak
     
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  3. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    They have various names. A slide switch such as you have would probably be called one pole three position or 1P3T. A similar toggle switch would be SPST On-off-on.

    I took a peak at Digikey for "slide switches." they do list a few non stocked Arcoelectric switches that meet your criteria. If you can find one they should be under 3 bucks a piece.

    Things don't get any better if you use an on-off-on toggle switch (center is off) type. These are also mostly non stock items but they do carry one for $4.54.
     
  4. SLK001

    Well-Known Member

    Nov 29, 2011
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    Find an old hair dryer. A lot of them have the HI-LO-OFF switch that you could use.
     
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  5. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    Is the switch you show in post #1 rated for mains voltage at 400mA? It doesn't look like it.
     
  6. MaxHeadRoom

    Expert

    Jul 18, 2013
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  7. Johann

    Senior Member

    Nov 27, 2006
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    For changing between full wave and half wave, this is all you need.
     
  8. Alec_t

    AAC Fanatic!

    Sep 17, 2013
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    What is the load you want to switch? If it's inductive (like a motor), then powering it with half-wave rectified mains voltage could let the magic smoke out.
     
    Last edited: Feb 19, 2016
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  9. Vindhyachal Takniki

    Thread Starter Member

    Nov 3, 2014
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    How about using the switch which is attached, it says 250vac/10A. I will select DP3T.
    In my circuit entire load is resistive+one 1N4007+500K resistor+led(as in tester)
     
  10. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    While I prefer to derate things by a larger margin a 250 volt switch can handle 220 volts.

    One obscure thing about switches is a high current switch such as yours may not work reliably for low currents, and they need a bit of current to literally burn off any oxide that forms at the point of contact. Your test jig may stop or go intermittent after a bit. Or not... Just wanted to mention this point just in case.
     
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