UL 60947-9-2:2020 is an international standard that defines the functionality and performance requirements for low-voltage switchgear and controlgear inside electrical distribution systems. It specifically focuses on devices known as "motor-starters", which are used to control electric motors.
Scope and Purpose
The scope of UL 60947-9-2:2020 is to ensure that motor-starters meet safety, reliability, and efficiency standards. These devices play a crucial role in protecting both the motor and the connected equipment from potential damage caused by electrical faults or abnormal operating conditions.
Motor-starters are widely used in various industrial and commercial applications, including manufacturing plants, utilities, transportation, and building infrastructure. Therefore, ensuring their compliance with the designated safety standards is of paramount importance.
Key Requirements
UL 60947-9-2:2020 outlines several essential requirements that motor-starters need to meet. These include:
Electrical Safety: The standard mandates various tests and criteria to verify the device's ability to withstand electrical stresses without failure. This includes insulation resistance, dielectric strength, short-circuit withstand capability, and the ability to handle overcurrent conditions.
Thermal Performance: Motor-starters are subjected to different thermal stresses during operation. The standard sets criteria to assess their ability to dissipate heat and maintain proper functioning under specified temperature limits.
Mechanical Endurance: Motor-starters undergo frequent switching operations. The standard specifies test methods to ensure their mechanical components can withstand the intended number of operations without failure.
Clearances and Creepage Distances: To prevent electric shocks and reduce the risk of short circuits, UL 60947-9-2:2020 defines specific clearances and creepage distances between live parts and accessible conductive parts.
Environmental Conditions: The standard accounts for various environmental factors, such as temperature, humidity, vibration, and altitude, to ensure motor-starters can perform reliably under different operating conditions.
Benefits and Impact
Complying with UL 60947-9-2:2020 brings several benefits to manufacturers, end-users, and regulatory bodies. Firstly, it enhances the overall safety of electrical systems by reducing the risk of electrical hazards, fires, and equipment damage.
Secondly, the standard promotes interoperability between different motor-starters, enabling seamless integration within complex electrical installations. This simplifies system design and maintenance processes, resulting in cost savings and improved productivity.
Lastly, UL 60947-9-2:2020 ensures global harmonization in terms of safety requirements, allowing manufacturers to access multiple international markets without additional certification burdens. It also facilitates compliance with local regulations and supports sustainable development initiatives focused on energy efficiency and resource conservation.
Nina She