UL/CSA Fuse Classifications

Class	Voltage	Current Range	Interrupting Rating	Description / Application
Class CC	600V	0–30A	200 kA	Small-dimension, rejection-type. Control circuits, branch circuits.
Class CF	600V	0–100A	300 kA	Compact, high-performance. Motor control centers.
Class G	480V	0–60A	100 kA	Small-dimension. Branch circuit, motor protection.
Class H	250/600V	0–600A	10 kA	Renewable (one-time or renewable). Older installations.
Class J	600V	0–600A	200 kA	Current-limiting, rejection-type. General purpose, high fault.
Class K	250/600V	0–600A	50–200 kA	Current-limiting (K1, K5, K9 sub-classes). General purpose.
Class L	600V	601–6000A	200 kA	Current-limiting, bolt-in. Main bus, large feeders.
Class R	250/600V	0–600A	200–300 kA	Current-limiting, rejection-type (RK1, RK5). Branch circuits.
Class RK1	250/600V	0–600A	200 kA	High current-limiting. Motor circuits, transformers.
Class RK5	250/600V	0–600A	200 kA	Moderate current-limiting. General branch circuits.
Class T	300/600V	0–1200A	200 kA	Very fast-acting, compact. Space-limited applications.
Class CD	600V	0–600A	200 kA	Time-delay, current-limiting. Motor starters.
Midget	250/600V	0–30A	10–100 kA	13/32" × 1-1/2" size. Control circuits, instruments.
Supplemental	125–600V	0–60A	10 kA	Not branch-circuit rated. Internal equipment protection.
Semiconductor	600V	0–600A	200 kA	Ultra-fast (aR equivalent). Drives, rectifiers, SCRs.

🏷️ UL/CSA Fuse Classifications