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ASCO Model 485 Surge Protective Device

120–600 VAC | 600–900 kA/Phase

The ASCO Model 485 Surge Protective Device is our largest, highest kA (SPD). The Model 485 utilises two separate, dual redundant replaceable modules that work in parallel. It features large block, 50 kA thermally protected MOVs with surge current levels of 600–900 kA per phase. This unit is for "mission-critical" environments.

ASCO Model 485 Surge Protective Device
  • Features

    • UL 1449 Fourth Edition Listed
    • Directly Connected, Discrete Protection Elements Between All Possible Modes
    • 600–900 kA per phase ratings
    • All UL required OCP and Safety Coordination included inside:
    • – Type 1 SPDs intended for Line or Load Side of Main Disconnect
      – Type 2 SPDs intended for Load Side of Main Disconnect
    • 20 kA Inominal (In) (most models)
    • 200 kA SCCRs (most models)
    • UL 96A Lightning Protection Master Label compliant
    • Rotary Disconnect Switch Included as Standard
    • Includes Audible Alarm, Silence Switch and Form C Dry Contacts


    • AC sinewave tracking filter with EMI/RFI filtering up to -50 dB from 10 kHz to 100 MHz
    • (Type 2 option only, incl. UL 1283 listing)
    • Dual redundant replaceable modules with large block 50 kA thermal protected MOVs
    • Phase loss monitoring (toggles LED and dry contacts)
    • Standard NEMA 1/12/4 with 3R drains enclosure
    • Voltage specific design – highly configurable
    • All MOV suppression elements monitored
    • 10-year warranty


    • Banking, Financial and Insurance
    • Broadcast and Entertainment
    • Chemical/Petrochemical (excl. Oil and Gas)
    • Construction and Engineering
    • Data Centre/Colocation/Hosting
    • Education
    • Fire/Alarm/Security
    • Government
    • Healthcare
    • Manufacturing
    • Marine
    • Military, Defence, Aerospace and Missile
    • Mining/Metals
    • Nuclear Power
    • Oil and Gas
    • Power Generation
    • Power/Gas Transmission and Distribution
    • Professional Services
    • Retail and Wholesale
    • Telecom
    • Transportation
    • Water Supply/Sewage Disposal

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