The Allen-Bradley 140U-K3D3-D35 UL Molded Case Circuit Breaker is a high-performance circuit breaker that is designed to protect industrial control panel circuits from the damage caused by a current overload or short circuit. This device features a high interrupting rating within a compact, cost-effective package, and it is ideal for control applications where there is limited panel space. The 140U-K3D3-D35 Circuit Breaker is designed for industrial applications like the Control Circuits, Feeder Circuits, HACR (heating, air conditioning, and refrigeration), and the high-intensity-discharge applications. It is also designed for back-feeding at 480 and 240 Volts AC. The 140U-K3D3-D35 Circuit Breaker has a voltage supply rating of 480 Volts AC with an operating range of 240 to 600 Volts AC, and it has a maximum trip rating of 350 Amps. This device has a maximum interrupting of 35 Kilo-Amps and an impulse withstand rating of 6.0 Kilo-Volts. It has an insulation voltage rating of 750 Volts and a mechanical life cycle rating of 100,000 operations.

The 140U-K3D3-D35 Circuit Breaker is designed with a fixed thermal/adjustable magnetic protection unit that provides fixed thermal overload protection and an instantaneous short-circuit trip protection. The 140U-K3D3-D35 Circuit Breaker uses a bimetallic element that trips the breaker contact when it is heated by an increasing load, and it uses an electromagnetic coil that produces a magnetic field that is proportional to the applied current to instantaneously trip the breaker. The 140U-K3D3-D35 Circuit Breaker is fitted with factory-standard bolt-on terminal screws and terminal lugs must be ordered separately if they are needed. It has an open type of enclosure, and it must be used within a -8 to 60 degrees Celsius temperature range.