Which of the following is NOT a feature of a PLR?

• A. Solid state control device
• B. Easy to program
• C. Has internal counters and timers
• D. Designed primarily for industrial use

Answer: (D)

A PLR combines logic and actuation in a compact, often solid-state control device. It’s designed to be easy to program so you can implement basic relay-style logic without complex programming, and it typically includes internal counters and timers to handle sequencing, delays, and pulse counting right inside the unit. These capabilities—solid-state control, straightforward programming, and built-in timing and counting functions—are the defining features that make a PLR useful for automation tasks.

The statement about being designed primarily for industrial use describes the typical market and application domain rather than a technical capability of the device. While PLRs are commonly used in industrial controls, this phrasing isn’t a functional feature of the device itself, and PLRs can be applied in other contexts as well. That makes it the choice that is not a feature of a PLR.