Overview
The Allen-Bradley 140M-C2E-B40 is part of the Bulletin 140M motor protection circuit breaker (MPCB) family from Rockwell Automation. This C-frame, 3-pole breaker combines manual switching, adjustable overload protection, and fixed magnetic short-circuit protection in a single compact DIN-rail-mounted device. Rated for 600 VAC, 50/60 Hz operation, it serves as a complete motor branch-circuit protector suitable for small to medium motors in industrial automation, machine tools, packaging equipment, and production control panels.
Key Features
- Adjustable Thermal Trip: 2.5–4 A range allows precise calibration to motor full-load current requirements for optimal overload response.
- Fixed Magnetic Protection: Standard magnetic trip at 13× rated current provides rapid short-circuit detection and automatic disconnection to protect wiring and downstream equipment.
- Manual Switching: Rotary knob operation permits safe, direct motor disconnect without auxiliary contactors.
- Class 10 Trip Response: Thermal overload trips within 10 seconds, reducing equipment damage and downtime.
- UL/CSA Dual Listing: Listed as Type E Manual Self-Protected Combination Motor Controller or standalone Circuit Breaker, providing single-device compliance for branch-circuit protection and motor control under NEC/CEC requirements.
- DIN Rail Mounting: Compact footprint (3.5″ L × 3.7″ W × 2.4″ H) enables space-efficient control panel integration.
Technical Specifications
- Current Range (Thermal Trip): 2.5–4.0 A adjustable
- Magnetic Trip Setting: Fixed at 13 × Ie (short-circuit protection)
- Frame Size: C
- Number of Poles: 3
- Voltage Rating: 600 VAC
- Frequency: 50/60 Hz
- Interrupting Rating: 100 kAIC (standard breaking capacity)
- Mounting: DIN rail
- Trip Type: Thermal-magnetic (adjustable thermal + fixed magnetic)
- Dimensions: 3.5″ L × 3.7″ W × 2.4″ H
- Weight: 0.71 lb (333 g)
- Trip Classification: Class 10 (trips ≤10 seconds at 3× thermal setting)
- Application Category: CAT A (utilization category A for motor loads)
- Operating Frequency: 50/60 Hz
- Certifications: UL, CSA, CCC
Typical Applications
- Motor branch-circuit protection and disconnection in industrial machinery
- Small-to-medium three-phase AC motor control (1.5–3 HP equivalent)
- Machine tool tables, conveyors, and production equipment
- Manufacturing automation panels and OEM control enclosures
- Backup or replacement motor starter in retrofit applications
- Group installation scenarios where tap-conductor protection is required
Compatibility & Replacements
The 140M-C2E-B40 is part of the Allen-Bradley 140M series and is compatible with standard 140M accessories, including:
Related Models: 140M-C2E-B25 (2.5 A), 140M-C2E-B63 (6.3 A), 140M-D8E-B25 (D-frame variant).
Rockwell Compatibility: Works alongside Allen-Bradley 100-C contactors in Type E self-protected combination motor controller configurations per NEC Article 430-81 and CEC Rule 28-200.
Installation Note: When combined with a 100-C contactor, both components must pass 6000 electrical and 4000 mechanical operational tests to achieve weld-free, certified performance. Drop-in replacement for equivalent 3-pole, 2.5–4 A thermal-magnetic breakers in DIN rail applications; verify voltage and current ratings before installation.
