Which statement best describes non-retentive timers?

Which statement best describes non-retentive timers?

• A. They accumulate when energized, but reset whenever the input is de-energized
• B. They retain accumulated time after power down
• C. They require a separate reset instruction
• D. They never reset

Answer: (D)

Non-retentive timers count up only while their input is energized, and they reset back to zero as soon as the input is de-energized. They do not keep the accumulated time if power is lost, which distinguishes them from retentive timers. So the best description is that they accumulate when energized and reset whenever the input becomes false. The idea that they retain time after power down would describe retentive behavior, and they do reset when the triggering condition ends, so saying they never reset isn’t correct.

Non-retentive timers count up only while their input is energized, and they reset back to zero as soon as the input is de-energized. They do not keep the accumulated time if power is lost, which distinguishes them from retentive timers. So the best description is that they accumulate when energized and reset whenever the input becomes false. The idea that they retain time after power down would describe retentive behavior, and they do reset when the triggering condition ends, so saying they never reset isn’t correct.