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ks_oo

Member Since: January 15, 2009

Country: United States

  • I usually use a reed relay and two diodes. It seems like this design is very popular in Europe. This design ensures that there will be no voltage drop.
    http://img297.imageshack.us/my.php?image=relayrf2.png
    D8 and D9 are standard diodes with 0.7V drop.
    When you plug it in normally, current will travel through D8 into the solenoid. The reed relay will close and current will flow through into your circuit board.
    If someone plugs it backwards, D9 will allow current to flow through to D8 and the reed relay won’t get activated.

  • I usually use a reed relay and two diodes. It seems like this design is very popular in Europe. This design ensures that there will be no voltage drop.
    http://img297.imageshack.us/img297/3342/relayrf2.th.png
    D8 and D9 are standard diodes with 0.7V drop.
    When you plug it in normally, current will travel through D8 into the solenoid. The reed relay will close and current will flow through into your circuit board.
    If someone plugs it backwards, D9 will allow current to flow through to D8 and the reed relay won’t get activated.

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