A short circuit in a power distribution board can cause immense damage to the equipment and shutdown processes for weeks. This is important as OEMs and panel builders need to consider short circuit capacity for industrial operations while using less energy and space.
According to Schneider Electric, more customers are asking for control and electrical panels built to a higher short circuit capacity rating. The end goal is to create a safer environment whilst increasing power and efficiency. Across commerce and industry, end users are seeking more compact and configurable panels to provide flexibility for smaller plant rooms and fault capacities up to 50 kA.
Industrial control panel manufacturers design custom products for thousands of applications. To comply with BS EN 61439-2 assemblies must meet minimum safety and performance standards including short circuit capacity.
Designing for high short circuit capacity
For panel builders the component with the lowest short circuit capacity limits the capacity for the whole panel, which includes components like motor controls, overload relays and circuit breakers. Having wide ratings on contactors and overloads allows OEMs to use circuit breakers rather than fuses for high interrupting capacity installation.
Designing panels to 50 kA as standard allows a standardised baseline requiring fewer engineering changes. For a lower short circuit capacity panel, engineers have the option to substitute components with a lower interrupting rating to save material costs and increase the profit on a project.
The key is aligning with a manufacturer having a comprehensive product range to meet a variety of short circuit capacities. New generations of motor starters and upgraded circuit breakers by Schneider Electric meet this need. Moreover, the motor control innovations also create more digitisation opportunities that support the integration of motor management into asset management. This provides end users with flexibility of design and the ability to use advanced services and analytic tools.
New generations of power components.
Schneider Electric’s new TeSys Deca and Giga series motor starters have improved short circuit ratings to provide greater versatility. Furthermore, the starters and circuit breakers designs reduce engineering time and complexity. At the same time, they improve machine reliability and drive down maintenance costs. For example, TeSys Deca GV2 series starters and offer market-leading type 2 coordination at over 50 kA at 415V.
The short circuit capacity is of concern to end users given its importance in safety and compliance. PowerPacT moulded case circuit breakers offer interrupting capacities from 18–200 kA at 415V. Recent enhancements to the entire line of circuit breakers have also resulted in improved troubleshooting and operations. Configurable settings improve overload relay protection, earth fault protection, and phase imbalance protection.
Design optimisation in motor controls offers increased flexibility to meet the growing demand for products that are easy to install. Contactors with wide coil voltage ranges and wide range overload relays with configurable protection selections enable a higher degree of field application with the benefit of reducing inventory part numbers. These innovations can also reduce costs while accommodating higher short circuit capacities. Furthermore, TeSys Giga contactors accept a PLC input for reducing power supply ratings even when using high power contactors.