Positive AC energy for track indicator light?

• A. Te
• B. TeCx
• C. TeBx
• D. Tb

Answer: (C)

Understanding how energy polarity and the feeding path to a track indicator light are designated in signaling notation is essential. For a positive AC energy supply to a track indicator, the notation must indicate track energy, the energizing function, the specific branch, and the positive polarity marker. The option that combines these is TeBx: T for track, e for energizing source, B for the branch feeding the indicator, and x to denote the positive half-cycle of the AC supply. This shows the indicator receives positive AC energy from the B branch. The other possibilities either omit the branch designation (Te), imply a different circuit element like a capacitor path (TeCx), or refer to a different track component altogether (Tb), so they don’t specify the required positive energy path for the indicator.