Wiring and componentsQuestion 9 of 1506

Which failure mode is most common for a solid-state relay output?

It fails open
It fails with the coil shorted to the load
It fails shorted (closed)
It fails by welding the armature

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Correct answer: It fails shorted (closed)

Solid-state outputs tend to fail shorted, while electromechanical contacts tend to fail open.

Source: Lessons in Electric Circuits IV: Digital (Kuphaldt), 5.5: Solid-state Relays

Questions last reviewed: 18 October 2026

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