Overview
The LPJ-8SP Class J fuse is a dual-element, time-delay current-limiting fuse manufactured by Eaton Bussmann. It delivers 300kA interrupting rating at 600 Vac and 100kA at 300 Vdc, making it one of the highest-capacity Class J fuses available. Separate overload and short-circuit elements provide protective time delay tailored for high inrush load applications, from HVAC compressors to motor controllers.
Key Features
- Dual-element, time-delay design: 10-second minimum hold time at 500% rated current prevents nuisance trips from transient inrush
- 300kA/100kA interrupting rating: Highest protection rating in Class J, UL and CSA certified
- 2-to-1 selective coordination ratio: Within the Low-Peak family, prevents electrical shutdowns from extending beyond the failed circuit
- Current-limiting technology: Reduces stress on downstream components during fault conditions
- Compact cartridge form factor: Ferrule terminals (0.81 in diameter × 2.25 in length) fit standard Class J holders
Technical Specifications
- Amperage Rating: 8 A
- Voltage Rating: 600 Vac / 300 Vdc
- Interrupting Rating: 300 kA Vac RMS (Symmetrical), 100 kA Vdc
- Fuse Class: UL Class J
- Type: Dual-element, time-delay, current-limiting
- Time Delay: 10 seconds minimum at 500% of rated current
- Body Diameter: 0.81 inches
- Body Length: 2.25 inches
- Terminal Type: Ferrule
- Body Material: Melamine
- Mounting: Class J fuse holder or socket
- Standards: UL 248-8, CSA C22.2 No. 248.8, RoHS Compliant
- Series: Bussmann Low-Peak LPJ-SP
Typical Applications
The LPJ-8SP is commonly used in:
- Commercial HVAC and refrigeration circuits requiring inrush tolerance
- Motor control centers and variable frequency drive (VFD) input protection
- Backup generator and UPS distribution panels
- Industrial machinery branch circuits with solenoid or transformer inrush
- Critical facility power distribution where selective coordination is essential
- Replacement or upgrade of older non-current-limiting Class J fuses
Compatibility & Replacements
Compatible With
- Class J fuse holders and rejection-type sockets
- Industrial control panels rated 600V/300V DC
- Three-phase and single-phase branch circuits
- Series-rated combination systems with branch circuit breakers
- Any Class J application compliant with UL 248-8 or CSA C22.2 No. 248.8
Replaces / Drop-In Replacement For
- Older Bussmann Low-Peak LPJ-8SP non-indicating versions
- Generic Class J 8A time-delay fuses with lower interrupting ratings
- Single-element or non-current-limiting Class J 8A fuses
Works With
- Class J fuse clips and 600V industrial switchgear
- UL-listed and CSA-certified power distribution equipment
- Commercial electrical systems rated at 600V or below
- Branch circuit coordination schemes using the 2-to-1 LPJ family ratios
