140M-C2T-B63 | Allen-Bradley | Bulletin 140M Motor Protection Circuit Breaker

Product Overview

The Allen-Bradley 140M-C2T-B63 acts as a specialized, Frame C Motor Protection Circuit Breaker (MPCB) within the Bulletin 140M family. This molded case hardware component provides localized, downstream isolation and defense for single-phase or three-phase industrial motors against damaging overloads and high-current short circuits.

While the original manufacturer has discontinued this specific series, we supply this essential component strictly as a 100% brand new, original factory-sealed unit. This ensures clean, unpitted physical contacts and intact factory calibration for plant operators seeking direct, drop-in replacements for obsolete control loops.

Technical Specifications

The table below maps out the precise trip ratings, frame classification, and physical profile of this motor protector:

Engineering Advantages

• Combines Dual Protection in One Housing: The integrated thermal-magnetic architecture combines two vital safety behaviors. The adjustable bi-metal strip tracks winding heat to deflect during persistent low-level overloads, while the fixed magnetic coil triggers instantaneous tripping during high-current phase-to-phase shorts, saving valuable DIN rail space.

• Allows Precision Overcurrent Tuning: An integrated front-facing dial adjusts the thermal trip threshold between 4.0 A and 6.3 A. Engineers calibrate this dial to mirror the exact Full Load Amps (FLA) printed on the target motor's nameplate, preventing nuisance trips during startup while providing tight thermal boundaries under full factory load.

• Simplifies Legacy Panel Drop-In Upgrades: The standard Frame C layout mounts directly onto 35mm top-hat DIN rails or pairs with legacy 140M line-side terminal adaptors. This eliminates the need to re-drill backplanes, modify copper bus bars, or alter existing motor starter wiring schemes when substituting a damaged old-generation breaker.

FAQs

• Can I use this discontinued 140M-C2T-B63 breaker to replace newer Allen-Bradley 140G or 140MT models?

  This brand new 140M-C2T-B63 serves as a direct drop-in replacement for existing Bulletin 140M control arrays. Newer 140MT series lines feature updated spacing and terminal positions. To avoid modifying your existing bus bars or supply spacers, stick with this original 140M unit if your cabinet uses legacy Frame C spacing.

• What are the proper wire preparation steps to ensure reliable power connections at the terminals?

  Strip your motor power wires to the factory-specified length, avoiding nicked strands. Insert the bare copper fully into the pressure box terminals, ensuring no insulation gets trapped beneath the clamp screw. Torque the terminal screws to the recommended value to prevent high-resistance micro-arcing under high motor startup current draws.

• Does this unit protect three-phase motors against phase loss conditions?

  Yes. The internal differential trip mechanism senses asymmetrical current draws. If one phase drops out completely due to an upstream fuse blow, the internal link bars unlatch the mechanism faster than a standard single-phase overload block, separating the contacts before unbalanced currents overheat the motor windings.