The 140U-KTD3-D30 circuit breaker is a molded case circuit breaker manufactured by Allen-Bradley/Rockwell Automation as part of the 140U MCB series. It has a K Frame size with a current rating of 400 Amps. The circuit breaker also features a trip unit with fixed thermal as well as adjustable magnetic protection. The Allen-Bradley 140U-KTD3-D30 circuit breaker has three poles with a current rating of up to 3000 Amps. At 300 Amps of operational current, this circuit breaker has a fixed thermal trip adjustment rating of 300 Amps and a magnetic trip adjustment range of 1500 to 3000 Amps. It also features interrupting ratings of 65 kiloamps at 380 to 415 Volts, 35 kiloamps at 600 Volts, 65 kiloamps at 480 Volts, and 13 kiloamps at 690 Volts. Other features of the K Frame circuit breakers include molded case switches, flex cable operators, field-installed internal control modules, and rotary operators.

The Allen-Bradley 140U-KTD3-D30 molded case circuit breaker is rated and approved for compliance with the UL 489, UL, CSA, IEC, CE, and KEMA-KEUR standards. Other features include field or factory-installed accessories, high interrupting ratings in compact dimensions, and global approvals and listings for universal applications across the world. Additionally, it has flex cable operating devices as well as rotary variable-depth operating mechanisms. The 140U-KTD3-D30 circuit breaker has a thermal-magnetic current range of 15 to 800 Amps, a molded case switch current range of 125 to 1200 Amps, and an electronic current range of 70 to 1200 Amps with options including long time or short time settings, long time or short time or high instantaneous settings, long time or short time or ground fault settings, and long time or short time or high instantaneous or ground fault settings.