Bussmann JJN-300 T-Tron Fuse (300 Amp) Review March 25, 2019 - Paladino Bussmann Class T-Tron Fuse, 300 Amp. Extremely fast short-circuit response. Voltage rating: 15-600 Amp 160-Vdc. Interrupting rating: 20,000 Amp dc at 160-Vdc.