The 140U-K6X3 circuit breaker is a molded case circuit breaker manufactured by Allen Bradley/Rockwell Automation as part of the 140U MCB product line. It belongs to the bulletin 140U circuit breaker product line and it comes with a K Frame rating with a current of 400 Amps. At 480 Volts, this drive has an interrupting rating or breaking capacity of 60 to 69 kiloamps. The 140U-K6X3 circuit breaker has the frame-only protection type and three poles. Some of the common features of this breaker include a current range of 15 to 1200 Amps, with a thermal-magnetic current of 15 to 800 Amps, an electric current of 70 to 1200 Amps, and a molded case switched current of 125 to 1200 Amps. Other features are the flex cable operating mechanism, factory or field-installed accessories, high interrupting rating in compact dimensions, and the rotary variable depth operating mechanisms. This circuit breaker conforms to the UL 489, IEC 60947-2, and CSA 22.2, No.5 standards, and it is globally approved and rated for worldwide application.

The Allen-Bradley 140U-K6X3 circuit breaker has a K Frame at 50 Hertz frequency, and 400 Amps of current. It also has a breaking capacity of 100 kiloamps at 220 to 240 Volts, 65 kiloamps at 380 to 415 Volts, 50 or 38 kiloamps at 500 Volts, and 13 or 6 kiloamps at 690 Volts. At 60 Hertz and 400 Amps, this circuit breaker has an interrupting rating of 100 kiloamps at 240 Volts, 65 kiloamps at 480 Volts, and 35 kiloamps at 600 Volts. Other accessories for the 140U-K6X3 circuit breaker are the auxiliary contact that electrically indicates the "on" and "off" status of the breakers, and the alarm contact that electrically indicates the "tripped" status of the breaker. There are also shunt trips, an auxiliary and alarm contact combination, and an under-voltage release.