The 140U-H6C3-D11-A Molded Case Circuit Breaker by Allen-Bradley/ Rockwell Automation offers protection against overcurrents to equipment and conductors when they automatically open due to a current that reaches a certain level that results in extreme temperatures in the conductors or the insulation of the conductors. The molded case circuit breaker can also connect to the control panel as the main means of protection. This kind of protection involves short-circuit current protection and protection when overcurrent levels are low. In the industrial control panel applications, the molded case circuit breaker is used to offer protection against overcurrent. This protection can be split into two types that protect devices against thermal overcurrent and against short-circuiting. The 140U-H6C3-D11-A Molded Case Circuit Breaker has only one auxiliary contact (AX) and other internal modules such as the alarm contact (AL), a combination of the auxiliary and alarm contacts (AX/AL), shunt trip (SNT), and the undervoltage release (UVT) modules. The accessories can either be field installed or factory installed. The Allen-Bradley circuit breakers like this one have a maximum ambient temperature rating of 40 degrees Celsius without derating.

The 140U-H6C3-D11-A Molded Case Circuit Breaker complies with various standards including the CE, CSA 22,2 (No. 5), CCC (3-pole MCCBs), UL 489, IEC 60947-2 and KEMA (3-pole MCCBs) standards. The 140U molded case circuit breakers have also passed the IEC standard ratings, which makes the devices appropriate for safe use in harsh conditions such as hot and humid environments according to the IEC 60721-2-1 specifications. The 140U-H6C3-D11-A Molded Case Circuit Breaker has zinc plating with conversion layers to offer protection, metallic parts containing anti-corrosion protection, electronic circuits with protection against condensation, and glass fiber moldings to offer reinforcement. The circuit breakers are also tested for shock resistance to comply with the IEC 60068-2-27 standards and tested for vibration resistance to comply with the IEC 60068-2-6 resistance.