Beginner 02 — Two switches (AND)
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Briefing
Two switches in series. The light only turns on when SWITCH_1 AND SWITCH_2 are both ON. If either is OFF the light is OFF. This is how interlocks work — guard-closed AND start-pressed, both required to start the motor. Series contacts read as AND.
Objectives
- When both SWITCH_1 and SWITCH_2 are true, LIGHT turns on
- When either is false, LIGHT stays off
Hints
- Place two normally-open contacts in series — SWITCH_1 then SWITCH_2 — on the same rung.
- Both contacts must close before energy reaches the coil.
I/O Table
Inputs
SWITCH_1First switch (NO)
BOOL · %I0.0
SWITCH_2Second switch (NO)
BOOL · %I0.1
Outputs
LIGHTIndicator lamp
BOOL · %Q0.0
Your program will be tested against:
All test cases run automatically when you submit. Assertions are hidden until you pass.
- #1Only SWITCH_1 on → LIGHT off
Either switch open keeps the light off
- #2Both switches on → LIGHT on
Both switches closed turns on the light
- #3Both off → LIGHT off
Both switches open keeps the light off
Related scenarios
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