Which code corresponds to Positive lead to track transformer?

• A. Tp
• B. Ttbx
• C. Ttcx
• D. Ug

Answer: (B)

In signaling equipment, codes for leads are built from a device prefix plus letters that show the function of that lead. A transformer-related lead starts with a T, flagging it as part of the transformer circuit. The positive lead to the track transformer is identified by the combination that matches the track-transformer positive-connection role in the standard labeling table, which is represented by the Ttbx designation. This distinguishes it from other codes that refer to different functions, such as a general supply voltage (Ug) or other transformer/track terminal configurations that don’t indicate the positive lead. So the Ttbx label is the one that uniquely denotes the positive lead to the track transformer.