In PLR programming, two switches in parallel are described as which?

In PLR programming, two switches in parallel are described as which?

• A. S1 with S2
• B. S1 or S2
• C. S1 and S2
• D. S1 without S2

Answer: (B)

In this kind of control logic, wiring two switches in parallel means either switch being closed will complete the circuit. That creates an OR condition: the output is energized if S1 is closed, or S2 is closed, or both. So the description that fits is S1 or S2. If both are closed, it’s still the same OR behavior, just redundantly closed. The other phrasings don’t match the parallel setup: “S1 with S2” or “S1 and S2” imply both must be closed at the same time (an AND condition), while “S1 without S2” means only S1 controls the output, not the parallel arrangement.

In this kind of control logic, wiring two switches in parallel means either switch being closed will complete the circuit. That creates an OR condition: the output is energized if S1 is closed, or S2 is closed, or both. So the description that fits is S1 or S2. If both are closed, it’s still the same OR behavior, just redundantly closed.

The other phrasings don’t match the parallel setup: “S1 with S2” or “S1 and S2” imply both must be closed at the same time (an AND condition), while “S1 without S2” means only S1 controls the output, not the parallel arrangement.