What is a loop analyzer used for?

Answer: C — Troubleshooting traffic signal loops

A loop analyzer is an essential tool specifically designed for troubleshooting traffic signal loops. These loops, often embedded in roadways, are critical for detecting vehicles and determining when to change traffic signals. The loop analyzer performs several key functions that assist technicians in diagnosing issues related to these detection systems. When a traffic signal system experiences malfunctions—such as failure to detect vehicles, intermittent operation, or erroneous signal changes—technicians use the loop analyzer to assess the condition of the loop itself. This involves checking the loop's integrity, its electromagnetic characteristics, and ensuring that the wiring connections are functioning properly. By analyzing the loop's performance, technicians can determine if it is operational or if repairs or replacements are needed. In contrast, measuring voltage or resistance does not directly address the specifics of loop functionality within traffic signal systems, nor does testing battery life pertain to the function of detection loops. Therefore, the focus of the loop analyzer on troubleshooting makes it the correct choice.