Amtrak Signal Maintenance Training – Level 1 (SMT-1) Practice Test 2026 - Free Signal Maintenance Practice Questions and Study Guide

The code after relay positions describes how the two contacts (back and front) behave in the two states of the relay coil: de-energized and energized, and it also notes whether the relay can provide a code. The correct description fits a coding relay where the back contact changes with energization, while the front contact remains energized in the described condition, and the device is capable of coding. Specifically, when de-energized, the back is de-energized; when energized, the back is energized; the front is energized in the described state, and the relay is capable of coding. This matches the expected behavior of a coding relay used to produce a code from relay positions. The other options conflict with how a coding relay operates—for example, implying energization in the de-energized state, or claiming the relay cannot code—so they don’t describe the correct behavior.