Fuses are not the best choice to provide motor overload protection because of the high inrush current when starting.

• A. True
• B. False
• C. Only for DC applications
• D. Fuses are the best choice for motor protection

Answer: (A)

When protecting a motor, the control system needs to respond to overheating caused by overload, not just to brief current spikes. A motor draws a large inrush current when starting—often several times the running current. Fuses are mainly for short‑circuit protection and they melt after their current exceeds a rating for a certain time. That means using a fuse to handle motor overload can be problematic: if the fuse is sized to tolerate the startup surge, it won’t reliably trip on an actual overload; if it’s sized to protect against overload, it may nuisance trip during normal startup. So fuses aren’t well-suited to provide proper motor overload protection. In practice, motors are protected by devices designed for motor overload, such as thermal or electronic overload relays (often in combination with fuses that handle short-circuit protection).