The statement "The negative conductor of a two-wire supply shall be bonded to a good ground source" is true.

The statement "The negative conductor of a two-wire supply shall be bonded to a good ground source" is true.

• A. True
• B. False
• C. Not specified
• D. Only for grounded systems

Answer: (B)

In power-limited two-wire fire alarm circuits, the return path (the negative conductor) is not normally bonded to earth. These circuits are designed to be isolated from ground to avoid creating ground fault currents and potential nuisance alarms. Protective grounding is applied to metal enclosures and equipment through the earth conductor, but the DC return itself should generally remain floating unless a specific manufacturer instruction or code requirement dictates otherwise. That’s why the statement is not correct.

In power-limited two-wire fire alarm circuits, the return path (the negative conductor) is not normally bonded to earth. These circuits are designed to be isolated from ground to avoid creating ground fault currents and potential nuisance alarms. Protective grounding is applied to metal enclosures and equipment through the earth conductor, but the DC return itself should generally remain floating unless a specific manufacturer instruction or code requirement dictates otherwise. That’s why the statement is not correct.