Dust-Ignition-Proof Motor describes a totally enclosed motor that excludes ignitable dust and prevents arcs, sparks, or heat from ignition of exterior accumulations.

• A. Explosion-Proof Motor
• B. Dripproof Guarded Motor
• C. Dripproof Motor
• D. A totally enclosed motor that excludes ignitable dust and prevents ignition by arcs or sparks

Answer: (D)

Dust-ignition-proof motors are built for environments with ignitable dust. They have a totally enclosed housing to stop dust from entering, and their construction prevents arcs, sparks, or heat inside the motor from igniting any exterior dust accumulations. The description in the option matches this exact idea: a totally enclosed motor that excludes ignitable dust and prevents ignition by arcs or sparks. Explosion-proof motors focus on containing any internal explosion and are not specifically about preventing ignition of exterior dust, while dripproof and guarded ratings address water or physical protection, not dust ignition.