Overview
The Shawmut OT40 40A fuse is a one-time general-purpose low-voltage fuse designed to protect feeder and branch circuits serving lighting, heating, and other non-motor loads. This lot includes 16 units in new condition, offering reliable overload and short-circuit protection for industrial and commercial electrical systems.
Key Features
- Class K5 current-limiting fuse for reliable protection
- One-time (non-renewable) design for automatic circuit disconnection
- 50,000 ampere interrupting rating at all voltage levels
- Dual voltage rating: 250VAC and 250VDC compatible
- Fast-acting response to overcurrent conditions
- Ferrule terminal construction for secure panel mounting
- UL 248-9 and CSA C22.2 certified
Technical Specifications
| Ampere Rating | 40A |
| Voltage Rating | 250VAC / 250VDC |
| Fuse Type | One-Time (OT) |
| Interrupting Rating | 50 kA AC |
| Class | Class K5 |
| Terminal Type | Ferrule |
| Length | 3 inches |
| Diameter | 13/16 inch |
| Response Time | Fast-Acting |
| Certifications | UL 248-9, CSA C22.2 |
| Manufacturer | Ferraz Shawmut (Mersen) |
| Quantity per Lot | 16 units |
Typical Applications
- Industrial control panels and distribution equipment
- Lighting circuit protection in commercial buildings
- HVAC and heating system circuits
- General-purpose branch circuit protection
- Feeder circuit overcurrent protection
- Equipment rated for 250V single-phase or DC systems
Compatibility & Replacements
Compatible With
- Industrial control systems rated for 250VAC/250VDC
- Panelboard and distribution equipment designed for Class K5 fuses
- Motor control centers with auxiliary circuits
- Transformers and auxiliary equipment protection
- Electrical systems requiring 40A branch circuit protection
Replaces / Drop-In Replacement For
- Eaton Cooper Bussmann NON-40
- Littelfuse NLN040
- Reliance 64676-K
- Gould Shawmut OT40 (equivalent)
Works With
- Standard cartridge fuse holders and clips
- Industrial panelboards and switchgear
- Feeder and branch circuit protection schemes
- Equipment rated for Class K5 or Class K fuses










