Medium-Voltage Installation & Testing Built for Reliability
Safe, efficient, and NEC-compliant medium-voltage solutions to keep your facility powered with confidence.
Medium-voltage electrical systems are the backbone of industrial and commercial operations, and precision is critical to ensure safety, efficiency, and compliance. With over 43 years of experience, SEI provides expert installation, testing, and maintenance for medium-voltage infrastructure keeping your facility running smoothly while meeting NEC and UL standards.
Our Medium-Voltage Services
Installation & Upgrades
- We install and upgrade medium-voltage systems with precision, ensuring seamless integration and long-term reliability.
Comprehensive Testing & Troubleshooting
- Our advanced testing procedures detect potential issues before they become costly failures, ensuring system integrity and peak performance.
Preventative Maintenance & Repairs
- Proactive maintenance helps prevent downtime, while our expert repair services restore power quickly when issues arise.
Code Compliance & Safety Assurance
- Every project is completed to meet NEC, UL, and industry safety standards, protecting your facility and workforce.
Why Choose SEI?
- 43+ years of expertise in medium-voltage systems.
- NEC- & UL-compliant solutions for maximum safety and performance.
- Reliable installation, testing, and troubleshooting to minimize downtime.
- Commitment to precision and expert craftsmanship in every project.
The future of energy begins now
Reimagining the power of energy.
Ensure your medium-voltage systems are safe, reliable, and operating at peak efficiency.
With SEI, you get more than an electrical contractor you get a trusted partner dedicated to the reliability and safety of your medium-voltage infrastructure.
Frequently Asked Questions
Detailed commissioning reports, test results (insulation, grounding, protective device testing), as-built drawings (if applicable), maintenance logs, maintenance plans or recommendations, and compliance documentation as needed for your records and audits.
Absolutely. We offer system upgrades, reconfigurations, capacity expansions, and retrofits applying the same level of planning, testing, and code compliance as with new installations.
Facilities with high power demand such as manufacturing plants, data centers, warehouses, industrial sites, large commercial buildings, hospitals, water treatment plants, and any infrastructure requiring heavy-duty power distribution benefit from MV systems.
Yes. All our installations and services are designed and executed to comply with NEC, UL, and applicable safety regulations. We also consider grounding, fault-protection, arc-flash mitigation, and safe equipment layout to protect both your facility and personnel.
It depends on the facility’s usage, load profile, and environmental conditions. Many providers recommend regular inspections and preventative maintenance at least annually, or more frequently if the system is critical or heavily used. Maintenance often includes thermal imaging, insulation testing, ground checks, equipment inspections, relay testing and calibration, and cleaning or replacement of worn components.
Because MV systems power critical loads, improper installation or undetected cable/termination faults can lead to equipment damage, fire, downtime, or safety hazards. Proper testing (such as insulation tests, hipot or VLF tests, grounding checks, protective device testing, and partial-discharge analysis) ensures the system is safe, reliable, and compliant before energization. Many MV contractors offer comprehensive testing and commissioning services.
Medium-voltage typically covers systems from 1 kV up to around 35 kV or higher, depending on local definitions. It’s the range between standard low-voltage building wiring and high-voltage transmission systems.
Detailed commissioning reports, test results (insulation, grounding, protective device testing), as-built drawings (if applicable), maintenance logs, maintenance plans or recommendations, and compliance documentation as needed for your records and audits.
Absolutely. We offer system upgrades, reconfigurations, capacity expansions, and retrofits applying the same level of planning, testing, and code compliance as with new installations.
Facilities with high power demand such as manufacturing plants, data centers, warehouses, industrial sites, large commercial buildings, hospitals, water treatment plants, and any infrastructure requiring heavy-duty power distribution benefit from MV systems.
Yes. All our installations and services are designed and executed to comply with NEC, UL, and applicable safety regulations. We also consider grounding, fault-protection, arc-flash mitigation, and safe equipment layout to protect both your facility and personnel.
It depends on the facility’s usage, load profile, and environmental conditions. Many providers recommend regular inspections and preventative maintenance at least annually, or more frequently if the system is critical or heavily used. Maintenance often includes thermal imaging, insulation testing, ground checks, equipment inspections, relay testing and calibration, and cleaning or replacement of worn components.
Because MV systems power critical loads, improper installation or undetected cable/termination faults can lead to equipment damage, fire, downtime, or safety hazards. Proper testing (such as insulation tests, hipot or VLF tests, grounding checks, protective device testing, and partial-discharge analysis) ensures the system is safe, reliable, and compliant before energization. Many MV contractors offer comprehensive testing and commissioning services.
Medium-voltage typically covers systems from 1 kV up to around 35 kV or higher, depending on local definitions. It’s the range between standard low-voltage building wiring and high-voltage transmission systems.