What is the purpose of a standby power supply?

• A. To test the pump.
• B. To lubricate bearings.
• C. To provide an alternate power source for the fire pump if the primary power fails.
• D. To improve efficiency.

Answer: (C)

The purpose of a standby power supply is to ensure the fire pump has an alternate source of power if the primary electrical power fails. In an emergency, this standby (often a generator or other independent power source) can automatically start and feed the pump, isolation valves, and control equipment so the system still delivers water or maintains pressure during a power outage. This reliability is essential because a fire event may coincide with a loss of utility power, and the pump must operate without human intervention when needed. It isn’t about testing the pump, lubricating bearings, or improving efficiency—the standby power supply is specifically to keep the pump or its control system powered during a power failure.