Fuse Characteristics: CLASS L
l lt 4001 5000 to l lt 801 1200
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) | i2t 100kA A2s (A2s) | i2t 200kA A2s (A2s) | i2t 300kA A2s (A2s) | i2t 50kA A2s (A2s) | peak lt 100kA A (A) | peak lt 200kA A (A) | peak lt 300kA A (A) | peak lt 50kA A (A) | peak lt function | standard | voltage rating V (V) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CLASS L | l lt 4001 5000 | 4001-5000 | 5,000 | 4,001 | — | 350,000,000 | 420,000,000 | — | — | 300,000 | 286,000 | — | Y = -1E-06X2 + 1.035X + 97000 | IEEE Std 3004.3-2020 | 600 |
| CLASS L | l lt 401 600 | 401-600 | 600 | 401 | 2,500,000 | 2,500,000 | 3,000,000 | 2,500,000 | 45,000 | 70,000 | 101,367 | 35,000 | Y = 3E-07X2 + 0.15X + 26667 | IEEE Std 3004.3-2020 | 600 |
| CLASS L | l lt 5001 6000 | 5001-6000 | 6,000 | 5,001 | — | 500,000,000 | 600,000,000 | — | — | 350,000 | 399,300 | — | — | IEEE Std 3004.3-2020 | 600 |
| CLASS L | l lt 601 800 | 601-800 | 800 | 601 | 10,000,000 | 10,000,000 | 12,000,000 | 10,000,000 | 80,000 | 80,000 | 79,200 | 80,000 | Y = 3E-07X2 + 0.3287X + 30712 | IEEE Std 3004.3-2020 | 600 |
| CLASS L | l lt 801 1200 | 801-1200 | 1,200 | 801 | 12,000,000 | 15,000,000 | 18,000,000 | 12,000,000 | 80,000 | 120,000 | 107,800 | 80,000 | Y = -4E-07X2 + 0.3206X + 48138 | IEEE Std 3004.3-2020 | 600 |
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