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More Comfort – More Performance – More Versatility

  • The ATC-900 is a programmable microprocessorbased monitoring device for use on Cat� transfer switches

  • It is a compact and self-contained panel-mounted device that is designed to replace traditional relay and solid-state logic panels

Technical Summary

Rating Range 120 to 600V, single phase and three phase @ 50/60 Hz
Switch Type Switch application dependent
Transfer Type Switch application dependent

ATC Controller Specifications

Enclosure Compatibility
  • NEMA 12 (std mounting)
  • NEMA 3R
  • UV Resistant Faceplate
  • Frequency Measurement Accuracy +/- 0.1 Hz
    Frequency Measurement Range 40 Hz to 80 Hz
    Frequency Measurements Of Source 1 and Source 2
    Input Control Voltage 120Vac (50/60 Hz) (operating range 65 to 160 Vac)
    Operating Humidity Up to 90% Relative Humidity (non-condensing)
    Operating Temperature Range -20 to 70 degree C (-4 to +158 degree F)
    Overfrequency Dropout Range 103 to 110% of Nominal System Frequency
    Overfrequency Pickup Range 101% to (Dropout +1 Hz) of nominal system frequency
    Underfrequency Dropout Range 90 to 97% of Nominal System Frequency
    Underfrequency Pickup Range (Dropout +1 Hz) to 99% of Nominal System Frequency
    Undervoltage Dropout Breaker Style 50 to 97% of Nominal System Voltage
    Contactor Style - 78 to 97%
    Undervoltage Pickup (Dropout +2%) to 99% of Nominal System Voltage
    Voltage Measurement Accuracy +/-1% of full scale
    Voltage Measurement Range 0 to 700 Vac
    Voltage Measurements of Utility Source 1, Source 2 and Load
    (VAB, VBC, VCA for Three Phase System)


    System Voltage Application 120 to 600 Vac (50/60 Hz) (single or three phase)

    Download resources

    ATC-900 Controller Spec Sheet
    Cat Gensets Rating Guide

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