The Square D A1.39 (JB) Thermal Unit is a crucial component in electrical protection systems designed to safeguard motors and other electrical equipment from overheating due to overload conditions. This thermal unit is specifically rated for a current range of 1.1 to 1.37 Amperes and belongs to Class 20 overload protection devices, which offer a delay feature to help manage inrush currents and reduce nuisance tripping during startup. Historically, Square D has been a leader in developing innovative electrical solutions, and their thermal units are recognized for reliability and efficiency in various industrial and commercial applications. The A1.39 thermal unit finds extensive use in environments such as manufacturing plants, machinery control systems, and heavy-duty electrical installations, where maintaining operational integrity is vital. Key features of the A1.39 include: - Adjustable current settings for tailored overload protection. - High resistance to environmental factors, enhancing durability and lifespan. - Fast response to overload conditions, ensuring immediate protection for equipment. - Compatibility with various types of motor starters, making it versatile for different applications.

Thermal Rating: 1.1-1.37 A Class: 20 Overload Protection Type: A1.39 Application: Motor Protection