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Is this the correct way to wire a rocker switch to LED strip?

schematic

simulate this circuit – Schematic created using CircuitLab

A lot of what I see online is people showing SPST 3-terminal switches for this application. Can I just use a 2-terminal like the one shown in the diagram?

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  • \$\begingroup\$ If your LED strip is compatible with 12V and your switch is rated to carry the LED current then I can't see a problem. \$\endgroup\$ – Andy aka Jul 7 '14 at 17:05
  • \$\begingroup\$ You can use 2-terminal switch. But you need to connect a resistor in series with the LED for limiting the current through it. \$\endgroup\$ – nidhin Jul 7 '14 at 17:07
  • \$\begingroup\$ I'm just a bit worried because all I see are 3-terminal switches being shown online. Would you always put the switch on the hot wire? \$\endgroup\$ – tazboy Jul 7 '14 at 17:07
  • \$\begingroup\$ The current is limited to 2 amps by the AC/DC adapter. \$\endgroup\$ – tazboy Jul 7 '14 at 17:07
  • \$\begingroup\$ A 2 terminal switch is just a 3 terminal switch with one contact cut off. Ignore the "normally closed" contact and just use the "common" and "normally open" contacts. \$\endgroup\$ – Majenko Jul 7 '14 at 17:09
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Assuming the LED strip works with the power supply alone, adding the switch in between is fine. The third terminal on a SPDT switch provides an alternate path for the power supply, but is usually not connected in this configuration regardless.

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  • \$\begingroup\$ I think I understand after re-watching a youtube video of someone using a third terminal. They ended up just connecting both ground wires to the same terminal which, I'm guessing, is just making it a SPST switch. Does that sound right? \$\endgroup\$ – tazboy Jul 7 '14 at 17:14
  • \$\begingroup\$ Also, are a lot of people incorrectly calling a 3-terminal switch a SPST, when it should be called a SPDT? \$\endgroup\$ – tazboy Jul 7 '14 at 17:15
  • \$\begingroup\$ "Single Pole (one common) Double Throw (two positions)". Three terminals total. It can be used to replace a SPST by leaving one of the throws unconnected, but it is still a SPDT. \$\endgroup\$ – Ignacio Vazquez-Abrams Jul 7 '14 at 17:17
  • \$\begingroup\$ I was checking out this person's video and others like it. youtube.com/watch?v=cQpQWFYX524 \$\endgroup\$ – tazboy Jul 7 '14 at 17:25
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The switch used in the video youtube.com/watch?v=cQpQWFYX524 is a lighted SPST switch. It includes an LED connected between one switch terminal and the third pin, as below.

schematic

simulate this circuit – Schematic created using CircuitLab

A plain SPST switch (no light) will only have two terminals. An unlighted switch with three terminals would be SPDT.

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