Overview
The Allen-Bradley 140U-H6C3-C50 is a 3-pole molded case circuit breaker from Rockwell Automation’s 140U series. This H-frame breaker is rated for 50A at 480V AC with fixed thermal and fixed magnetic trip functions, delivering 60–69kA interrupting capacity. The unit features non-interchangeable trip elements, load-side lug terminals, and bolt-on mounting for robust industrial motor control and branch protection applications.
Key Features
- Fixed Thermal/Magnetic Protection: Reliable long-time and instantaneous (LI) trip characteristics for motor and circuit protection.
- High Interrupting Rating: 60–69kA breaking capacity per UL 489 ensures protection in high-fault-current environments.
- H-Frame Design: Compact molded case suitable for panelboard and bolt-on mounting configurations.
- Non-Interchangeable Trip: Trip elements cannot be swapped, ensuring correct protection characteristics are maintained.
- Load-Side Lug Terminals: Factory-installed lug terminations simplify wiring and field installation.
- Current Limiting: Reduces downstream fault duty for enhanced system coordination.
Technical Specifications
- Rated Current: 50A
- Voltage Rating: 480V AC, 60Hz
- Number of Poles: 3-pole (3P)
- Frame Size: H-Frame
- Trip Type: Fixed Thermal/Fixed Magnetic (LI)
- Interrupting Capacity: 60–69kA @ 480V
- Mounting: Bolt-On
- Terminal Type: Load-Side Lug
- Current Limiting: Yes
- Certifications: UL 489, IEC 60947-2, CE, CSA C22.2 No. 235-95
Typical Applications
- Motor branch circuit protection in industrial control cabinets.
- Machine tool and production equipment power distribution.
- Panel-mounted overcurrent protection for AC circuits up to 480V.
- HVAC and compressor motor starter circuits.
- Coordination with soft starters and variable frequency drives (VFDs) in multi-motor systems.
Compatibility & Replacements
Compatible With
- Allen-Bradley 140U series panelboards and breaker frames
- Rockwell Automation motor control centers (MCCs)
- Industrial 480V AC 3-phase power distribution systems
- Standard panelboard mounting rails and bolt-on frames
Replaces / Drop-In Replacement For
- Earlier 140U-H series breaker configurations with equivalent 50A, 3-pole, 480V ratings
- Verify compatibility with system integrator or technical documentation before substitution
Works With
- Motor starters and soft starters (coordination via breaker sizing)
- VFDs and adjustable frequency drives (ASD)
- Control module combinations: Fixed thermal/magnetic trip cartridges only
- Supervisory monitoring systems (with auxiliary contacts if added)
