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ESP Digital QC Surge Protector/Noise Filter, 208-240 volt, 20 amp - Model E524ZNT

Ships in 6-8 weeks from the ESP factory in North Carolina

  • Model #: E524ZNT. Manufacturer: ESP
  • VERY IMPORTANT: Your equipment must have a NEMA 6-20P plug to work with this model. Please look at the plug photo to make sure it matches the plug on your machine.
  • Industrial-grade surge and noise protection: protect sensitive electronics from lightning strikes, surges, transients, noise and over voltage events
  • 208-240 volt / 20 amp with (1) 6-20R outlets
  • (RJ-45) network protection, (RJ-11) phone line protection
  • Professional protection at an affordable price
  • Endorsed and used by some of the world's biggest technology companies 

        Made in the USA

        ESP Surge Protector Product Comparison Chart

        • Voltage: 208-240VAC, Amperage: 20A
        • Input Connection: 3 foot cord with 6-20P plug
        • Output Connection: (1) 6-20R outlet
        • Patented Multi-Stage industrial surge/spike protection
        • Industrial EMI/RFI noise filtering
        • Catastrophic overvoltage protection
        • Wiring fault detection
        • ETL Cat5e Network surge protection (RJ-45)
        • Phone surge protection (RJ-11) with DSL filter
          • Lifetime Warranty on product
          • Lifetime Connected Equipment Warranty
          • Made in the USA

            Today's Digital QC is the evolution of the original, ground-breaking ESP design which came to market in the 1980s. To this day it remains one of the best selling professional-grade surge protectors in the world - having sold millions of units. It offers very powerful protection but without the advanced monitoring and diagnostic capability of the Next Gen and enVision products.

            Unlike standard surge protectors and power strips that use only metal oxide varistors (MOV), the Digital QC combines gas tubes, silicone avalanche diodes and metal oxide varistors into a patented circuit that does not degrade over time and provides very robust protection. 

            Like all ESP products, the Digital QC is proudly made in the USA with the highest quality components.

            The Digital QC offers comprehensive power protection to safeguard equipment from the dangers associated with damaging surges, spikes, over voltage, EMI/RFI noise and wiring faults.

            The Digital QC is available in a variety of voltage/amperage configurations. Many models also have Cat5e ETL verified network (RJ-45) and telephone line (RJ-11) surge protection to protect network interface circuits. The D5 series also includes power over Ethernet protection.

            Note: plug and outlet types as well as phone/network connections will vary from model to model. The product images may not illustrate the exact configurations.



              Physical Characteristics

              Dimensions - Length: 8.8"
              Dimensions - Width: 6.25"
              Dimensions - Height: 2.2"
              Shipping Weight: 3.4 lbs
              Input Connection: AC 3' cord with 6-20P plug
              Flexible Output Connection: 6 inch "pigtail" cord with (1) 6-20R outlet  

              Electrical Characteristics

              Maximum Line Voltage: 240VAC
              Maximum Load Current: 20A
              Leakage Current: <3.5 mA
              Steady State Efficiency: >99.2% @ 20A
              Thru-put Resistance: <0.030 Ohm
              Patented Hybrid Circuitry: Yes

              Voltage Suppression

              Response Time: < 25 nS
              Sine Wave Tracking: Yes
              Clamp Voltage 6kV 3kA - Normal Mode: 695V peak
              Clamp Voltage 6kV 3kA - Common Mode: 495V peak (L1-G)
              Clamp Voltage 6kV 3kA - Common Mode: 495V peak (L2-G)
              Maximum Surge Current Withstand for 20 μsec: 19500A peak
              Residual Energy Let-thru in Joules (less is better)
              -All Modes IEEE C62.41 Category A Ringwave: 0.33J
              -All Modes IEEE C62.41 Category B Ringwave: 0.33J
              -All Modes IEEE C62.41 Category B Impulse: 2.44J
              -All Modes UL 1449 Impulse: 0.43J
              --Total Residual Energy Let-thru All Modes: 3.53J
              Lowest UL 1449 Rating: 600V

              Frequency Attenuation

              Normal Mode
              >10 dB (3.16 times Reduction Factor): 5 kHz - 30 MHz
              >20 dB (10 times Reduction Factor): 45 kHz - 30 MHz
              >30 dB (31.6 times Reduction Factor): 55 kHz - 30 MHz
              >40 dB (100 times Reduction Factor): 70 kHz - 3.5 MHz
              Filter Order: 2nd
              Common Mode
              >10 dB (3.16 times Reduction Factor): 30 kHz - >30 MHz
              >20 dB (10 times Reduction Factor): 70 kHz - >30 MHz
              >30 dB (31.6 times Reduction Factor): 140 kHz - > 30 MHz
              >40 dB (100 times Reduction Factor): 220 MHz - 16 MHz
              Filter Order: 3rd
              Sine Wave Tracking: yes

              Telephone Line Suppression

              Connections: RJ-11 in/out
              Thru-put Resistance: 14 ohms
              Response Time: < 25 nS
              Clamp Voltage FCC Part 68 Metallic Waveform: 329V
              Clamp Voltage FCC Part 68 Longitudinal Waveform: 347V
              Maximum Surge Current Withstand for 160 μsec: 200A
              Residual Energy Let-thru in Joules
              -All Modes FCC Part 68 Longitudinal Waveform (less is better): 3.6J

              Network Protection

              Network Connections: RJ-45 in/out
              Protected Lines: all
              Clamp Voltage: 8V
              Peak Pulse Power: 1.5kW
              Response Time: <1 Pico Second
              Ethernet Data Transmission: Cat 5e 10/100/1000 Base Tx

              Approval Standards

              Best UL 1449 Rating in the Industry: 600 V
              Exceeds ANSI/IEEE C62.41 Catergory A&B: >10000 hits
              Withstands FCC Part 68 Surge Standard: Yes
              Complies with UL 497A & B Standards: Yes
              Complies with UL 498 Plug & Receptacles: Yes
              Complies with UL 991 Reliabilty Standard: N/A
              Complies with UL 1283 EMI Filter Standard Full EMI filter
              Safety Certified: UL-1449 Standard, ETL Listed