When replacing an open (blown) fuse a

• A. Use a higher rating fuse
• B. Replace with the same rating only
• C. Recommended capacity fuse should be used
• D. Ignore and continue

Answer: (C)

Understanding how fuses protect circuits is essential. A fuse is sized to interrupt current at a safe level for the wiring and components. When a fuse blows, it has done its job by opening the circuit before the current can cause damage. To maintain protection, you must replace it with the same rating as the original or with the manufacturer’s recommended capacity for that circuit. Using a fuse with a higher rating could permit the circuit to draw more current than the wiring can safely handle, risking overheating or fire. A lower rating would cause the fuse to blow again under normal operation or lead to nuisance failures. If you see a blown fuse, verify the intended load and check for faults in the circuit before replacing.