Bussmann EVH-350 | 350A 70VDC Fuse, 6kA AIC, MEGA Footprint

The Eaton Bussmann EVH-350 is a 350 A bolt-down DC fuse rated 70 VDC with a 6,000 A interrupting rating. Built to the ISO 20934 Type SF51 footprint, it uses the same 50.9 mm bolt spacing as a conventional MEGA fuse while carrying more than double the voltage rating and three times the breaking capacity. UL certified.

Why the 70 VDC rating matters

Most MEGA-format fuses are rated 32 VDC. A 48 V nominal LiFePO₄ bank charges to 58.4 V — well above that rating. DC faults have no zero-crossing to help quench the arc, so a fuse asked to interrupt above its rated voltage may not clear the fault. The EVH is rated 70 VDC, which covers 12 V, 24 V and 48 V nominal systems with margin.

Interrupting capacity and lithium banks

The 2025 revision to ABYC E-11 sets the interrupting-capacity requirement for lithium-ion batteries at 5,000 A for every 100 Ah of capacity, and calls for overcurrent protection at each individual battery on banks above 500 Ah. On that basis a 6,000 A device covers a single battery of roughly 120 Ah or less, and suits the per-battery position inside a larger bank. Main protection on a large bank still belongs to a Class T fuse sized to the whole bank.

These figures reflect our reading of the 2025 revision and are given for general guidance. Confirm the requirement against the current published standard for your application.

Specifications

Installation and continuous current

• Bolt centres 50.9 mm, overall length 68 mm, body height 9.9 mm — standard MEGA spacing.
• M8 terminal bolts. Torque to 20 N·m ±1. Do not overtorque; the terminals are tin-plated copper.
• Continuous rating note: Eaton characterises the 300–500 A EVH ratings as holding 75% of rated current for at least 4 hours. Size against your actual continuous load rather than assuming a full 350 A indefinitely.
• Opens in 1–15 s at 200% of rating and 0.5–5 s at 350%.

Typical applications

Large inverter and inverter/charger feeds, main DC distribution, high-output alternator and second-alternator circuits, thruster and windlass feeds, and any 48 V branch presently protected by a 32 V MEGA fuse.

This is not a substitute for a Class T fuse as the main overcurrent device on lithium banks above roughly 120 Ah, where the required interrupting capacity exceeds 6,000 A. Ampere rating and interrupting rating are separate questions — a 350 A fuse still only interrupts 6,000 A.

Not sure which rating you need? Jonsson Tech designs, installs and commissions these systems — send us your one-line and we will check it before you order.