Customer Support : (804) 355-1100

Matching SPD to Application


Applications should match Surge Protective Devices (SPDs) to the installation parameters which requires the evaluation of the surge protection and the electrical environment of the facility. A Site Shield Risk Assessment is a useful tool to perform this coordination. The proper cascading of surge protection is enhanced when using a coordinated specification.


THOR SYSTEMS’ Site Shield Risk Assessment provides the means to coordinate multiple SPD locations. During a Site Shield Survey, critical electrical equipment is reviewed and documented, providing the necessary information to identify a properly coordinated surge suppression system.

  • Modular Designs Offering – TSr Products
    Field Replaceable, upgradable modules
    50, 100, 150, 200, 250 and 300kA per mode (all modes protected)
    Applications: Service Entrance, Main Distribution, and where equipment criticality is a vital consideration
  • Non-modular Designs Offering – TSn Products
    Compact, non-field replaceable modules
    50, 100, and 150kA per mode (all modes protected)
    Applications: Lower ampacity Distribution, Sub-distribution, and Branch Panels

Schedule a Site Survey to create a Roadmap to Reliability for your company to reduce your maintenance expenses, improve the equipment process, enhance operating effectiveness and ongoing profitability.

Thank you for your time and interest in THOR SYSTEMS, INC. We look forward to becoming your Power Quality partner and resource for surge protection equipment. THOR SYSTEMS offers products and services that can protect you from the more obvious external to the more frequent internal transient voltage sources. Feel free to give us a call at 804.355.1100, visit our Web site or send an email to if you have any questions or would like additional information.



Electrical power quality problems cost the United States industries over $100 billion annually
80% of voltage surges and transients are caused by changes in electrical demand, inside the user's facility