What is the time base used by PLCs?

What is the time base used by PLCs?

• A. Milliseconds (0.001 s)
• B. Seconds
• C. Minutes
• D. Hours

Answer: (A)

Timing in PLCs hinges on a fixed smallest step, the time base, which is millisecond-scale. Most PLC timers count in discrete ticks of 1 millisecond, so you set delays and durations using milliseconds (0.001 s). For example, a 2-second delay is programmed as 2000 milliseconds. Minutes or hours aren’t the base timing unit; they are just longer durations expressed in milliseconds. This millisecond time base lets timers and pulse logic operate with fine, predictable granularity.

Timing in PLCs hinges on a fixed smallest step, the time base, which is millisecond-scale. Most PLC timers count in discrete ticks of 1 millisecond, so you set delays and durations using milliseconds (0.001 s). For example, a 2-second delay is programmed as 2000 milliseconds. Minutes or hours aren’t the base timing unit; they are just longer durations expressed in milliseconds. This millisecond time base lets timers and pulse logic operate with fine, predictable granularity.