Fuse Characteristics: CLASS J
j lt 0125A to j lt 0450A
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) | peak lt 100kA A (A) | standard | voltage rating V (V) |
|---|---|---|---|---|---|---|---|---|
| CLASS J | j lt 0125A | 125A | 125 | 125 | 150,000 | 15,500 | IEEE Std 3004.3-2020 | 600 |
| CLASS J | j lt 0150A | 150A | 150 | 150 | 175,000 | 17,000 | IEEE Std 3004.3-2020 | 600 |
| CLASS J | j lt 0175A | 175A | 175 | 175 | 225,000 | 18,500 | IEEE Std 3004.3-2020 | 600 |
| CLASS J | j lt 0225A | 225A | 225 | 225 | 350,000 | 22,500 | IEEE Std 3004.3-2020 | 600 |
| CLASS J | j lt 0250A | 250A | 250 | 250 | 450,000 | 24,000 | IEEE Std 3004.3-2020 | 600 |
| CLASS J | j lt 0300A | 300A | 300 | 300 | 600,000 | 26,000 | IEEE Std 3004.3-2020 | 600 |
| CLASS J | j lt 0350A | 350A | 350 | 350 | 800,000 | 29,000 | IEEE Std 3004.3-2020 | 600 |
| CLASS J | j lt 0450A | 450A | 450 | 450 | 1,500,000 | 36,000 | IEEE Std 3004.3-2020 | 600 |
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