Customer Support : (804) 355-1100

Other Things to Consider


Hybrid Design comprised of three elements (listed below) which, when combined, offer the optimum in Surge Protective Devices (SPDs): (Note: All Modular and Non-modular products are offered in one, two, or three element configurations.)

  • Thermally Protected Metal Oxide Varistors (TpMOVs) offering high energy handling “Fail Safe” technology with integrated thermal and dielectric (arc shield) protection
  • Silicon Avalanche Diodes (SADs) providing the most ideal suppression element and very fast reaction time (available in 1500W/mode or 15,000W/mode).
  • Filter Capacitors suppressing EMI/RFI electrical noise


  • Standard: Terminal Block, #6 AWG Wire, SPD fed from external 60A circuit breaker by customer
  • Option: Distribution Block, #2 AWG Wire, SPD fed from external 100A circuit breaker by customer
  • Option: Fused Disconnect, internal 60A by THOR SYSTEMS, INC.
  • Option: #6AWG Rope Lay (1050 strands) low impedance wire, improved performance 17 to 30% (recommend 30 ft/SPD installation)


Factory wired with #10 AWG Rope Lay Wire (413 strands), SPD fed from external 30A circuit breaker by customer





Bottom Feed, a popular (no cost adder) option, may be configured to mount directly on top of switchgear/switchboard/ATS keeping the conductors as short and straight as possible. The NEMA 4X enclosure provides a clear view of status indicating lights and total service access.










  • Status/Alarm Form “C” Contacts
  • Phase Loss Form “C” Contacts
  • Under/overvoltage and Phase Rotation Form “C” Contacts
  • Surge Counter:

Smart alphanumeric display (4) digit, 5×7 dot matrix, indicates total surge events:

  • Displays up to 27,000 events
  • Stores event in an EE PROM to ensure the event total is not lost if a power outage occurs
  • If there is a protection mode loss, display will alternate between the count total and an “ALRM” display


  • Surge Counter has (8) levels of sensitivity, allowing adjustment of the Counter trigger level by the end user
  • Sensitivity Level #3 is calibrated to increment using a combination (1.2µs x 50µs Voltage and 8µs x 20µs Current) waveform set at 500A.
  • Adjustment of each Sensitivity Level results in an approximate 80A increment from the previous setting (340A to 900A range).


  • The Extended Noise Filter Network is recommended for high Electromagnetic Interference/Radio Frequency Interference (EMI/RFI) environments. EMI/RFI is a known source of signal “crosstalk.”
  • High EMI environments would include applications with devices such as motors, fans, fluorescent lights, and transformers. RFI may originate from radio controlled equipment, stepper motor controls, CRTs, computers, walkie-talkies, public service communications or commercial broadcast stations.
  • The Extended Filter improves the operating effectiveness of equipment and processes by eliminating unnecessary restarts and reboots.


Although not always considered a part of the installation environment, Features and Benefits are an important aspect of the product application process. Along with exposure levels and equipment location categories, features and benefits may drive the selection of a particular model or system. Features or benefits promoting serviceability, performance, inter-connectability and available system information may influence the choice of a certain series or product selection. The installation environment may dictate certain features, e.g., an installation in a high exposure environment with extremely critical equipment may require a disconnect switch as well as field replaceable suppression elements, thus providing the means to be back online quickly in the event of a suppression system fault.

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