SC-40 EATON BUSSMANN FUSE

SC-40 EATON BUSSMANN FUSE – Industrial 40A 480VAC/300VDC Class G Time-Delay Fuse

The SC-40 EATON BUSSMANN FUSE (Model SC-40) is an industrial-grade, current-limiting Class G time-delay power fuse manufactured by Eaton’s Bussmann series. Engineered specifically for branch circuit protection, lighting loads, heating circuits, and industrial control equipment, this $40text{-amp}$ , $480text{ VAC} / 300text{ VDC}$ fuse provides high-level overcurrent and short-circuit protection in a compact cylindrical ferrule footprint.

Featuring a dual-element, time-delay mechanism, the SC-40 EATON BUSSMANN FUSE delivers a minimum 12-second time-delay at $200%$ of its rated current. This built-in delay allows temporary inductive startup surges and inrush currents from lighting ballasts or small motors to pass safely without nuisance tripping, while rapidly interrupting severe short circuits up to $100text{ kA RMS}$ Symmetrical at $480text{ VAC}$ (and $10text{ kA}$ at $300text{ VDC}$ ). Incorporating Class G physical size rejection, its length ( $2.25text{ inches}$ ) varies deterministically based on its ampacity rating to prevent the insertion of lower-voltage or higher-ampacity fuses into protected circuits.

As shown in the image, the fuse features a durable melamine tube body with clear labeling reading “Bussmann GENERAL PURPOSE SC 400Vac / 170Vdc” (with full UL ratings of $480text{ VAC}$ and $300text{ VDC}$ ), terminated on both ends with heavy-duty nickel-plated brass ferrule contact caps.

Key Features of the SC-40 EATON BUSSMANN FUSE

Class G Size Rejection Feature: Engineered with standardized Class G length dimensions ( $0.41'' text{ Dia} times 2.25'' text{ L}$ ) to prevent over-fusing or substituting incorrect voltage-rated components.
12-Second Time-Delay Performance: Sustains a minimum $12text{-second}$ time-delay at $200%$ current overload to absorb temporary electrical surges without premature opening.
High $100text{ kA}$ Interrupting Capacity: Fully rated for an interrupting rating of $100text{ kA RMS}$ Symmetrical at $480text{ VAC}$ and $10text{ kA}$ at $300text{ VDC}$ for superior fault mitigation.
Compact Space-Saving Design: Delivers full $480text{ V}$ Class G protection in a significantly smaller physical package than traditional Class H or Class RK5 branch fuses.
Advanced Current Limitation: Rapidly limits thermal ( $I^2t$ ) and electromechanical peak let-through energy under short-circuit conditions, protecting downstream components.
Robust Melamine Body: High-density melamine casing provides high arc-quenching capability, dimensional stability, and high thermal resistance under heavy electrical loads.

Common Applications and Practical Usage

The reliable time-delay response and compact rejection profile of the SC-40 EATON BUSSMANN FUSE make it a preferred choice across commercial and industrial distribution panels:

HVAC & Commercial Air Handling Equipment: Protects compressor controls, condenser fans, and electric heater coils in rooftop units.
Lighting Branch Circuits: Provides localized current-limiting protection for fluorescent, HID, and LED commercial lighting panelboards.
Industrial Control Cabinets: Protects branch feeders, control power supplies, solenoids, and contactors in $480text{ V}$ control enclosures.
Electric Heating Loads: Ideal for resistive heating elements and non-inductive industrial process circuits requiring high interrupting capacity.

Technical Specifications

The core electrical, physical, and compliance parameters for the SC-40 EATON BUSSMANN FUSE are detailed below:

Parameter Specification	Technical Details & Operational Values
Component Classification	Industrial Class G Time-Delay Fuse
Primary Target Keyword	SC-40 EATON BUSSMANN FUSE
Brand / Series	Eaton Bussmann Series / SC Series
Catalog Model / Part No.	SC-40
Amperage Rating	$40text{ Amps}$ ( $40text{ A}$ )
Voltage Rating	$480text{ VAC}$ / $300text{ VDC}$
Interrupt Rating (IR)	$100text{ kA RMS}$ Symmetrical at $480text{ VAC}$ / $10text{ kA}$ at $300text{ VDC}$
Response Characteristic	Time-Delay (Min. $12text{ seconds}$ at $200%$ current)
Fuse Class & Form Factor	UL Class G Ferrule ( $0.41'' times 2.25''$ / $10.3text{ mm} times 57.2text{ mm}$ )
Terminal Connection Type	Cylindrical Ferrule Caps
Body Material & Caps	Melamine Casing with Plated End Caps
Agency Certifications	UL Listed (Std 248-5, Guide JDDZ), CSA Certified, CE, RoHS Compliant

Operating Guidelines and Usage Tips

SAFETY NOTICE: Always isolate power sources and verify circuits are fully de-energized using a calibrated voltage tester prior to inspecting or replacing fuses.

Holder Compatibility: Always pair with dedicated Class G fuse blocks or panelboard clips designed for $40text{ A}$ Class G length dimensions to ensure proper rejection alignment.

Branch Circuit Sizing: Verify continuous loads do not exceed $80%$ of the fuse rating ( $32text{ A}$ ) for continuous duty applications in accordance with National Electrical Code (NEC®) standards.

To review official Class G current-limiting fuse specifications and branch circuit code requirements, consult the National Electrical Manufacturers Association (NEMA) Directory.

To check regional warehouse inventory availability or request commercial quotes for volume electrical fuses, visit the Control Qatar Contact Page.

SC-40 EATON BUSSMANN FUSE