The 140U-I3C3-D10 circuit breaker is a thermal-magnetic circuit breaker from the Centerline 2100 protection equipment series. It has been manufactured and distributed by Allen-Bradley. Breakers from this series are used to protect feeder circuits in different industrial applications such as those from a panel where motor loads are being fed, a panel where fixed loads are being fed by the breaker, and a panel where mixed loads are being protected by this breaker. The Allen-Bradley 140U-I3C3-D10 thermal-magnetic circuit breaker belongs to the Frame I product line and it comes with a moderate interrupting rating with a magnet trip range of 700 to 1400 Amps, a current rating of 125 Amps, and a voltage range that goes from 200 to 575 Volts. The Horsepower rating of the breaker goes from 20 to 50 Horsepower.

The Allen-Bradley 140U-I3C3-D10 thermal-magnetic circuit breaker achieves its best performance once the motor full load current reaches 15% of the Horsepower and voltage ratings of the breaker. This breaker comes with a NEMA starter size of 3. Some of the factors that need to be considered when selecting the installation location for the breaker are the type of conduits and busways that will be used, the height of the installation area, the breaker's alignment with other equipment, and the ambient temperature. All these factors need to be compatible with the breaker's NEMA 3 enclosure. The Allen-Bradley 140U-I3C3-D10 thermal-magnetic circuit breaker is equipped with optional and external mounting channels or it can be mounted on a pad. Once the breaker has tripped, it can be put back into operation once the current fault condition that provoked the action has been cleared.