Branch-circuit protection for motors and breakers for general loads. Results update as you type. Motor circuit builder
Motor
How this is worked out
- Maximums: inverse-time breaker 250% of full-load current, dual-element time-delay fuse 175%. Exception 1 allows the next standard size up.
- Recommended breaker: the standard ordinary-service selection for across-the-line starting, which allows for inrush. It's never shown above the code maximum.
- If the motor won't start on these sizes, the code allows more (up to 400% for breakers of 100 A or less, 300% above that, and 225% for time-delay fuses).
- Disconnect: at least 115% of full-load current.