Fuse Characteristics: CLASS T
t600 lt 0400A to t 600v
Fuse time-current characteristics, voltage ratings, interrupting capacity, and current-limiting classification by fuse class (UL 248 and IEC 60269). Also includes per-rating let-through current (peak A) and I²t (A²s) data from IEEE Std 3004.3-2020 for arc-flash and short-circuit coordination studies, covering Classes RK1, RK5, J, T (300V/600V), L, CC, G, CF, CD, C, CA, CB, mine-duty, and semiconductor fuse voltage derating.
| fuse class | record id | amp rating label | amp rating max (A) | amp rating min (A) | application | conventional fusing current factor (dimensionless) | conventional nonfusing current factor (dimensionless) | current limiting | dimensions ferrule blade | fuse type | i2t 100kA A2s (A2s) | i2t 200kA A2s (A2s) | i2t 50kA A2s (A2s) | interrupting rating kA ac (kA) | interrupting rating kA dc (kA) | peak lt 100kA A (A) | peak lt 200kA A (A) | peak lt 50kA A (A) | rejection feature | standard | time delay | voltage rating V (V) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CLASS T | t600 lt 0400A | 400A | 400 | 400 | — | — | — | — | — | — | 1,100,000 | 1,100,000 | 1,000,000 | — | — | 30,000 | 45,000 | 25,000 | — | IEEE Std 3004.3-2020 | — | 600 |
| CLASS T | t600 lt 0450A | 450A | 450 | 450 | — | — | — | — | — | — | 1,500,000 | — | — | — | — | 36,000 | — | — | — | IEEE Std 3004.3-2020 | — | 600 |
| CLASS T | t600 lt 0500A | 500A | 500 | 500 | — | — | — | — | — | — | 2,000,000 | — | — | — | — | 42,000 | — | — | — | IEEE Std 3004.3-2020 | — | 600 |
| CLASS T | t600 lt 0600A | 600A | 600 | 600 | — | — | — | — | — | — | 2,500,000 | 2,500,000 | 2,500,000 | — | — | 45,000 | 70,000 | 35,000 | — | IEEE Std 3004.3-2020 | — | 600 |
| CLASS T | t600 lt 0700A | 700A | 700 | 700 | — | — | — | — | — | — | 3,500,000 | — | — | — | — | 50,000 | — | — | — | IEEE Std 3004.3-2020 | — | 600 |
| CLASS T | t600 lt 0800A | 800A | 800 | 800 | — | — | — | — | — | — | 4,000,000 | 4,000,000 | 4,000,000 | — | — | 55,000 | 75,000 | 50,000 | — | IEEE Std 3004.3-2020 | — | 600 |
| CLASS T | t600 lt 1000A | 1000A | 1,000 | 1,000 | — | — | — | — | — | — | 8,000,000 | — | — | — | — | 65,000 | — | — | — | IEEE Std 3004.3-2020 | — | 600 |
| CLASS T | t600 lt 1200A | 1200A | 1,200 | 1,200 | — | — | — | — | — | — | 10,000,000 | 10,000,000 | 10,000,000 | — | — | 70,000 | 88,000 | 55,500 | — | IEEE Std 3004.3-2020 | — | 600 |
| CLASS T | t 300v | — | 1,200 | 0.1 | Class T 300VAC 0.1-1200A; very compact physical size vs Class J/L; dimensionally non-interchangeable; preferred for service entrance and large feeder protection where space is limited | 1.35 | 0.9 | current limiting | very compact ferrule or blade | T | — | — | — | 200 | 100 | — | — | — | none physically distinct | UL 248-15 | fast acting | 300 |
| CLASS T | t 600v | — | 1,200 | 0.1 | Class T 600VAC up to 1200A; bridges gap between Class J (max 600A) and Class L (from 601A); compact design; used in service entrance applications large motor feeders distribution panels | 1.35 | 0.9 | current limiting | very compact ferrule or blade | T | — | — | — | 200 | 100 | — | — | — | none physically distinct | UL 248-15 | fast acting | 600 |
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