No medium-voltage (MV) installation is identical. I’ve seen this firsthand while working on more than 300 projects with panel builders and customers. Since there’s no “one size fits all” approach to MV projects, it can be difficult for panel builders to design and integrate MV components while also meeting end-user specifications, site-specific constraints, and adapting to a wide range of technical and environmental factors. In addition, panel builders must consider if they will be adapting their existing MV equipment or creating entirely new assemblies, which can affect the installation. 

In this blog, I’ll highlight key areas to consider for successful MV component design and integration. 

What MV equipment components should panel builders prioritize? 

To ensure peak installation performance, panel builders’ efforts should concentrate on designing and integrating MV equipment’s core components. These include:  

• Circuit breakers  

• Load break switches 

• Contactors 

• Busbars for power connections 

• MV switchgear’s monitoring and control  

• Current transformers and voltage transformers  

• Insulation and enclosures  

What are key design and integration considerations? 

When designing MV switchgear assemblies, panel builders must take into account several considerations: 

• End-user specifications: Assemblies must meet customers’ precise needs while ensuring components integrate properly with existing infrastructure. 

• Safety: Safety is an important consideration in MV installation design. Panel builders must consider factors that can affect operator and equipment safety, such as dielectric withstand and mechanical interlocks, in early stages of component design and integration. 

• Installation environment: MV switchgear assembly design choices must match the conditions in which the MV equipment will be installed — indoors or outdoors, on the ground, in substations, etc.  

• Regulations and standards compliance: Panel builders must adhere to regional and international standards, such as IEC, when designing (e.g. LSC classifications Class PM or PI)., operating (Internal Arc Classification), and testing (ratings achieved) for MV equipment. For example, IEC 62271-200 is a key standard for defining MV switchgear safety and performance rules, such as ensuring service continuity during maintenance. 

• Ratings (Current, Voltage, Short circuit, etc.): Current, voltage, and short‑circuit ratings (including breaking capacity, short‑time withstand, and peak withstand) must match the site’s system conditions and protection coordination requirements. 

• Environmental considerations: To reduce MV equipment’s environmental impact, panel builders should prioritize using materials and designs that enhance durability, reduce carbon footprints, and extend product lifespans.  

Why is integration important?  

Once MV components are selected, the focus should shift to how well they perform together within the panel. Panel builders need to verify components’ electrical and mechanical performance and ensure that each component aligns with existing systems, meets required ratings and clearances, and supports safe operation. For example, early verification and simulation help check dielectric withstand and temperature rises before the panels are sent for formal testing.  

Integration is especially important when combining equipment from different suppliers or connecting new components to older installations because differences in design, standards, and compatibility can affect overall performance, safety, and reliability.  

Effective integration not only improves reliability but also reduces rework and shortens project delivery time. This occurs because integration can be verified before launching official validation in testing laboratories. 

Discover to how enhance MV component design and integration  

Schneider Electric experts can help panel builders select the best MV component solutions for their installation. We support panel builders in the integration, verification, and validation of MV components into their equipment (adapted or new).   

Learn more about component design and integration in our MV technical guide. The mySchneider portal also gives panel builders access to training centers, partner programs, and other mySchneider offers.  

About the author

Hervé PERRAUD, Application Design Principal Engineer

Hervé PERRAUD is an Application Design Principal Engineer at Schneider Electric with nearly 37 years of experience in Medium Voltage. Since 2016, he has been supporting MV panel builders worldwide by providing expert guidance on MV switchboard and cubicle design, component integration, and industrialization, helping partners deliver robust, compliant, and industrially optimized solutions.