Load break switches are essential components in electrical circuits, serving the critical function of breaking and making connections under load conditions. One of the prominent standards for these switches is the IEC / TS 60947-3, which focuses on AC / 23 fuse load break switches. These switches come in various types, notably the With / No type fuse load breaks, designed to facilitate switching in both AC and DC circuits. This adaptability enhances their versatility and usability across a range of applications.
These load break switches consist of fixed-contact blades and a distinctive contact system within the unit. This innovative design distributes the breaking energy between the contacts, effectively reducing contact surface combustion. The energy distribution between the contacts and arc extinguishing components in the load-breaking cells minimizes the formation of arcs and extends the contact life. This approach not only enhances the reliability of the switches but also contributes to operational safety.
In specific applications requiring higher amperage, such as in the 160 A range, disconnectors incorporate a friction and rotary system. This system ensures efficient current interruption by breaking the current at multiple points per phase. Moreover, certain designs, like the Federal load breakers, employ a rotary contact system that enables the switch to be opened to increase break capacity. This feature allows for the complete separation of plugs from the circuit, facilitating safe and hassle-free plug replacement.
Fused load breakers, rated between 160 A and 630 A, can be effectively used for short circuit protection with a 65 kA fuse. On the other hand, unfused load breakers are designed with a thermal air flow rating spanning from 160 A to 2000 A, accompanied by a short-term resistance capability ranging from 8 kA to 35 kA. These attributes make load break switches adaptable to a wide range of load conditions and electrical requirements.
Furthermore, manufacturers have taken user-friendliness into consideration by incorporating height-adjustable feet in these switches. This feature simplifies installation and maintenance, enabling users to optimize the positioning of the switches for their specific setups.
In conclusion, load break switches play a crucial role in electrical circuits, offering reliable switching capabilities even under load conditions. The IEC / TS 60947-3 standards guide the design and production of these switches, ensuring their compatibility with various circuit types. By incorporating innovative contact systems, enhanced energy distribution, and features like rotary contact systems, these switches demonstrate improved efficiency and safety. Their adaptability to different current ranges and load conditions, along with user-friendly design elements, cements load break switches as indispensable components in modern electrical systems.
This post was written by Justin Tidd, Director at Becker/SMC. For nearly a half a century, Becker Mining has been at the forefront of safety, producing the best load break switch in the industry. Becker/SMC is the industry’s leader in increasingly more sophisticated electrical control systems. Most of the major innovations, design features and specialized electrical components have been developed by Becker/SMC.