The Allen-Bradley 140U-K0X3 UL listed Molded Case Circuit Breaker is a circuit breaker frame from the K-frame circuit breaker family designed to provide short-circuit and overload protection to a wide arrange of industrial control panel applications. This 3-pole breaker frame belongs to the K-Frame breaker series, and it comes with a very compact and cost-effective design that is suitable for applications where panel space is limited. The 140U-K0X3 Circuit Breaker is suitable for back-feeding at 240 to 480 Volts AC, and it is suitable for industrial applications like distribution panels, feeder circuits (branch circuit protection), small cabinets applications, heaters, air conditioning, refrigeration (HACR), and high-intensity discharge applications like the HID lamps.

The 140U-K0X3 Circuit Breaker is a 480 Volts AC breaker frame with a 400 Amps frame rating and an interrupting rating of 100 Kilo-Amps at 480 Volts AC and 200 Kilo-Amps at 240 Volts AC. This frame supports a circuit with 240 to 600 Volts AC operating range, and it has a rated impulse withstand of 6000 Volts. The 140U-K0X3 Circuit Breaker has an electrical lifespan of about 10,000 operations and a mechanical lifespan of around 100,000 operations. This breaker does not come with a factory-installed protection unit. However, it supports both thermal/magnetic and electronic trip units. It also supports internal control modules like the auxiliary contact, alarm contact, under voltage release, and shunt trip. The 140U-K0X3 Circuit Breaker also supports a wide range of field-installable external accessories. The 140U-K0X3 Circuit Breaker can be used within a control panel enclosure and it is rated for use in a -8 to 60 degrees Celsius temperature range.