Which code denotes the normal relay used as a substitute for a lever in the normal position?

• A. Nlp
• B. Ns
• C. Nvp
• D. Nwc

Answer: (A)

In signaling practice, relays are labeled to show their role in interlocking and their state relative to a lever. The code for a normal relay that is specifically used as a substitute for a lever in its normal (rest) position directly communicates that function: a normal state (N) with a lever-related role (l) and the idea of position (p). This designation means the relay mirrors the lever’s resting condition and maintains the same electrical condition as the lever would when it is in its normal position, preserving safe and correct interlocking behavior even when the lever mechanism isn’t physically involved. The other codes would point to different functions or states that don’t describe a lever substitute, so they don’t fit the described role.