Which code is Power off relay?

• A. Pos
• B. Rg
• C. Po
• D. Nx

Answer: (C)

Recognizing relay state codes in signaling diagrams: Po is the label used to indicate a Power off condition, meaning the relay coil is de-energized. When power is removed, the relay releases and its contacts settle to the normal (rest) position, which is a common default state in many safety and signaling circuits. This makes Po the clear choice for “Power off relay.” The other codes—Pos, Rg, and Nx—do not denote power-off: Pos typically refers to a position or positive state, Rg isn’t a standard code for power-off, and Nx isn’t used to indicate power-off either.