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ASCO Model 318 Surge Protective Device

20-600VAC / 600-1000VDC(PV) | 25-50kA/Phase

The ASCO Model 318 DIN-Rail Mounted Surge Protective Device, makes it easy to embed state of the art transient protection into automated processes and provide protection for sensitive circuits. The ASCO Model 318 Surge Protective Devices use large block MOVs with a patented thermal detection circuit, eliminating the need for separate overcurrent fusing; allowing for a smaller footprint where space is an issue.

ASCO Model 318 Surge Protective Device
  • Features

    • UL 1449 Fourth Edition Recognized
    • Parallel Electrical Connection–Easy to install
    • 50kA per mode
    • All UL required OCP & Safety Coordination included inside – Supplemental Fusing/OCP Not Required
    • UL 1449-4: 20kA Inominal
    • UL 1449-4: 200kA SCCR


    • Large-Block 34mm sq. MOVs – Individually Fused & Thermally Protected
    • Diagnostic Monitoring - Visual Indicator Tabs
    • Optional Form C Normally Open/Closed Dry Contact
    • 5-Year Warranty


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