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When three switches are connected to a single output, there are some arrangements that are not strictly OR logic and not strictly AND logic.
Did you find a circuit box that had one switch that could shut off current to the output, while the other two were in the “on” position? This switch is commonly known as a “safety switch”, or a “kill switch”. Some circuit boxes had three separate safety switches, but some had only one.
Find the circuit box that had only one safety switch. What kind of logic did the other two switches use?
Open the box and see if you can find the junction that follows the safety switch and leads to the other two.
When would it be helpful to put a safety switch into an appliance?
