The Bulletin 140MT motor circuit protectors (specifically the D9N version) offered by Rockwell Automation have a magnetic short-circuit rating and are capable of handling currents up to 40A. These circuit protectors are designed to be used as part of three-component starters in conjunction with contactors and overload relays. One of the advantages of the 140MT motor circuit protectors is that they feature tap conductor ratings, which allow for the use of smaller conductors in group motor installations. This can result in cost savings for the installation. These motor circuit protectors undergo rigorous testing with contactors and overload relays to ensure high levels of short circuit protection. This ensures the safety and reliability of the overall motor control system.
The 140MT series extends the current range, with C-frame models supporting currents up to 32A and D-frame models supporting currents up to 40A. This expanded range enables the use of these circuit protectors in a wider variety of applications. Additionally, the 140MT motor circuit protectors offer improved thermal performance, resulting in reduced heat loss. This helps in maintaining the optimal operating conditions for the motor and contributes to overall energy efficiency. One of the notable features of the 140MT series is its higher short circuit ratings, allowing it to address more demanding applications that require robust short circuit protection.
By enabling the use of smaller conductors in group motor installations, the 140MT circuit protectors help reduce the installed cost of the motor control system. To simplify documentation and ensure compliance, Rockwell Automation provides an SCCR (Short-Circuit Current Rating) tool, which certifies the combination testing of the 140MT motor circuit protectors with 100-E, 100-C, and 100-K contactors. Overall, the Bulletin 140MT motor circuit protectors offer a comprehensive solution for motor control and protection, providing enhanced performance, flexibility, and cost savings in various industrial applications.
