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    Mission-Critical Facilities

    Fault-tolerant power solutions that you can depend on

    Mission Critical

    Reliable power is critical to nearly every business operation. Major organizations worldwide trust SEL to provide mission-critical power protection, communications, and management systems to ensure an uninterrupted supply of high-quality electric power. SEL’s comprehensive power management systems optimize power delivery and quickly reroute energy around faults to minimize production interruptions and save money.

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    Find Rep By Location

    SEL solutions are found in virtually every major domestic data center across Internet, enterprise, colocation, and wholesale data center segments.

    “I use SEL not just because of their industry-leading products and technical support,...but because SEL and its people are committed to doing the job right and making the user (me) happy with the end product.”
    -Tim Burttram, Plant Electrical Engineer & Senior Project Manager at Cascade Steel Rolling Mills

    “Reliability is a big issue due to the exposure a public utility has, and our local utility decided to swap out their other relays and go exclusively with the SEL-351 Relays. My recommendation (to choose SEL) wasn’t even challenged.”
    -Charlie Adams, Senior Engineer at Marathon Oil

    ”SEL's field technical support has been very valuable to me. During our upgrade project, I got fast and reliable technical answers. And that’s simply how good SEL support is. I know we can count on SEL for that level of support every time.”
    Don Elliott, Senior Engineer/Power Manger at Resolute Forest Products


    motorMAX Arc-Flash Protection

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    <span class="sm-caps">motorMAX</span> Arc-Flash Protection

    SEL Performance Class & Quality Assurance

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    SEL Performance Class & Quality Assurance

    SEL Reliability

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    SEL Reliability

    Related Solutions and Services


    Arc-Flash Solutions

    Life-saving protection at the speed of light


    Complete Engineering Services

    Designing, building, and commissioning complete power systems


    Advanced Power Metering

    Increasing energy efficiency


    Feeder Protection

    Versatile power protection for industrial feeder applications


    Generator Protection

    Complete primary and backup protection from all types of faults


    Precise Time

    Industry-leading accuracy, time distribution, and dependability


    Security for Critical Infrastructure

    Security-focused, preventative solutions you need and expect


    Industrial Automation Systems

    Improve system performance using SEL expertise