Overview
The Cooper Bussmann LPJ-100SP is a Class J Low-Peak time-delay, dual-element current-limiting fuse designed for motor control circuits and industrial branch circuit protection. Rated 100A at 600Vac/300Vdc with a 300 kA interrupting rating at 600Vac (100 kA at 300Vdc), this fuse combines overload and short-circuit protection in a single compact unit. The LPJ-100SP delivers reliable protection while minimizing unnecessary power shutdowns caused by transient inrush currents.
Key Features
- Dual-element time-delay design: 10-second minimum delay at 500% rated current allows high inrush loads (motors, transformers) to start without nuisance trips
- Current-limiting technology: Separate overload and short-circuit elements protect downstream components from damaging thermal and magnetic effects
- Selective coordination: 2:1 ampacity ratio within the Low-Peak fuse family prevents electrical shutdowns from extending beyond the failed circuit
- Class J rated: UL Listed and CSA Certified for low-voltage circuits; compatible with standard Class J fuse holders
- Compact form factor: Bolted blade terminal design fits standard industrial panel fuse holders
Technical Specifications
- Amperage: 100A
- Voltage Rating: 600Vac / 300Vdc
- Interrupting Rating: 300 kA @ 600Vac; 100 kA @ 300Vdc
- Response Time: 10 seconds (minimum) at 500% rated current
- Type: Dual-element, time-delay, non-indicating
- Fuse Class: Class J
- Terminal Type: Bolted blade
- Body Material: Melamine cartridge
- Dimensions: 1.13″ diameter × 4.63″ length (29mm × 118mm)
- Agency Approvals: UL Listed (Guide JDDZ, File E4273), CSA Certified (File 53787, CSA C22.2 No. 248.8)
- Series: LPJ-SP (Bussmann Low-Peak)
Typical Applications
- Motor branch circuits and motor control centers
- Machine tool and production equipment control circuits
- HVAC system protection and heating/cooling loads
- Industrial panel feeder and main circuit protection
- Three-phase and single-phase industrial distribution systems
- Series combination with branch circuit breakers for coordinated protection
Compatibility & Replacements
Compatible With
- Standard Class J fuse holders and clips
- Industrial control panels rated 600Vac or 300Vdc
- Motor starters and motor control centers
- Disconnect switches with Class J fuse provision
- Series-rated branch circuit breaker combinations
Replaces / Drop-In Replacement For
- Older Cooper Bussmann Low-Peak fuses in identical amperage rating
- Standard Class J fuses in 100A applications requiring time-delay performance
- Verify compatibility with system integrator; do not assume interchangeability with other manufacturers’ Class J fuses without engineering review
Works With
- UL 508 industrial control panel designs
- NEMA MG-1 motor control systems
- IEC motor control and distribution equipment
- Class J-rated disconnect and combination starters
- Any Class J fuse holder or Class J-compliant electrical system
