This post contains basic 3 Way and 4 Way lighting control Switch Loop Schematics.

With a "Complete" closed circuit, the Lamp is shown to be "On". If the Lamp is shown to be "Off", the circuit is open via one or more switches.

Schematics set #1; 3-Way Light Control Switch Loops:

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Lamp "Off"

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Lamp "On"


Schematics set #2; 3 / 4 Way Lighting Control Switch Loops:

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Lamp "Off"

[Linked Image]
Lamp "Off"

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Lamp "On"

[Linked Image]
Lamp "On"

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!