Overview
The Square D JJL36250M75 is a PowerPact J-Frame motor circuit protector (MCP) designed for industrial motor protection and short-circuit defense. Rated at 250A, 3-pole, 600VAC with a 25kA interrupting capacity at rated voltage, this unit provides instantaneous-trip protection while accommodating transient motor inrush without nuisance tripping. The JJL36250M75 combines thermal-magnetic trip technology with rugged molded-case construction for reliable performance in general-purpose motor applications.
Key Features
- Instantaneous-Trip Design: Protects motors from short-circuit faults while accepting normal inrush current without unwanted shutdowns
- Thermal-Magnetic Trip Unit: Dual-element protection responds to overloads (thermal) and short circuits (magnetic instantaneous)
- Line/Load Lugs: Both sides equipped with line and load terminals for direct wire connections (3/0 AWG to 350 kcmil)
- Unit Mount Configuration: Space-efficient design accommodates standardized equipment layouts
- Multi-Standard Compliance: UL 489, CSA C22.2 #5-02, IEC 60947-2, NEC-listed for North American installations
- Interchangeable Accessories: Compatible with PowerPact J circuit breaker field-installable trip units and accessories
Technical Specifications
- Rated Current: 250A continuous at 80% of rating per NEC/CEC
- Voltage Rating: 600 VAC, 50/60 Hz
- Poles: 3
- Interrupting Rating (SCCR): 25 kA @ 600 VAC; 65 kA @ 480 VAC; 100 kA @ 240 VAC
- Trip Range: 684–2500A (magnetic instantaneous)
- Wire Size Range: 3/0 AWG to 350 kcmil
- Mounting: Unit Mount (flex-mounted into panelboard)
- Handle Type: Toggle handle actuator
- Dimensions: 7.52 in (H) × 4.12 in (W) × 5 in (D)
- Ambient Temperature Rating: 104°F (40°C) free-air reference; trip element calibrated at 40°C
- Frame Size: JJ (250A)
- Terminal Type: Line/Load Lug
- Certifications: UL 489, CSA C22.2 #5-02, IEC 60947-2, CE/CCC Marked, Federal Spec W-C-375B/GEN
Typical Applications
- Squirrel-cage induction motors in industrial pump, fan, and compressor systems
- General-purpose motor circuits requiring short-circuit and overload coordination
- Panelboard motor control centers (MCCs) and distributed motor protection
- HVAC equipment motor starters and soft-start drive protection
- Textile, food processing, and manufacturing production lines
- Predictive maintenance systems requiring reliable nuisance-trip-free operation
Compatibility & Replacements
Compatible With
- Square D PowerPact J-Frame switchgear and panelboards
- Molded-case circuit breaker cubicle assemblies rated for 250A, 600VAC
- Standard UL 489 motor control center terminals and bussing
- Field-installable trip units (S29451 Overcurrent Actuator, compatible Micrologic units)
- Open-door shaft operators for manual control integration
- Motor starting contactors and soft-start variable frequency drives (as line-side protection)
Replaces / Drop-In Replacement For
- Earlier PowerPact J 250A thermal-magnetic MCP models with same lug configuration
- Direct interchange with legacy Square D JJ-frame 250A motor protectors in existing panel layouts
- Note: Verify frame-size and terminal compatibility before installation. Contact your system integrator for specific model cross-reference if replacing competitor products.
Works With
- Square D EcoStruxure Power monitoring and analytics software (via optional communication modules)
- Standard three-pole motor starters (manual and magnetic contactor types)
- IEC 60947-2 compliant motor control schemes
- Both thermal-element and electronic (Micrologic) trip unit ecosystems in PowerPact J series




