Motor controlsQuestion 232 of 1506

How does a modern electronic time-delay relay make its delay?

  1. A heated bimetal strip that bends
  2. A pneumatic dashpot slows the armature
  3. A fluid-filled piston and spring
  4. An RC network times the delay
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Correct answer: An RC network times the delay

Older relays used pneumatic dashpots. Newer ones use resistor-capacitor circuits.

Source: Lessons in Electric Circuits IV: Digital (Kuphaldt), 5.3: Time-delay Relays

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Questions last reviewed: 18 October 2026