Beginner 03 — Two switches (OR)
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Briefing
Two switches in parallel. The light turns on when SWITCH_1 OR SWITCH_2 is ON. Either one is enough. This is how you wire two start buttons — front-of-machine and back-of-machine — so an operator on either side can run the line. Parallel contacts read as OR.
Objectives
- When SWITCH_1 is true, LIGHT turns on
- When SWITCH_2 is true, LIGHT turns on
- When both are false, LIGHT stays off
Hints
- Place two normally-open contacts in parallel — one above the other on a branch.
- Energy can take either path through the rung; either contact closing energises 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.
- #1SWITCH_2 only → LIGHT on
Either switch closed lights the lamp
- #2SWITCH_1 only → LIGHT on
Either switch closed lights the lamp
- #3Both off → LIGHT off
Both switches open keeps the light off
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