The ATC-300+ is a comprehensive and multifunctional microprocessor-based ATS controller. It is a compact and self-contained panel-mounted device that is designed to replace traditional relay and solid-state logic panels. The ATC-300+ Controller provides programmed flexibility to address the needs of any system. It operates from all system voltages between 120 to 600V, single-phase and three-phase at 50 or 60 Hz. In addition, a period of no control power is provided. The controller monitors the condition of the three-phase line-to-line voltage and frequency of Source 1 and Source 2 power sources and can be programmed for single-phase operation. The ATC-300+ Controller provides the intelligence to ensure that the ATS operates properly through a series of programmed sensing and timing functions.

Technical Summary
Rating Range120 to 600V, single phase and three phase @ 50/60 Hz
Transfer TypeSwitch application dependent
Switch TypeSwitch application dependent
ATC Controller Specifications
Input Control Voltage65 to 145 Vac 50/60 hZ
Voltage Measurements of UtilitySource 1 VAB Source 2 VAB
Source 1 VAC Source 2 VBC
Source 1 VCA Source 2 VCA
Voltage Measurement Range0 to 790 VAC rms (50/60 Hz)
Voltage Measurement Accuracy+/-2% of nominal input voltage
Frequency Measurements OfSource 1 and Source 2
Frequency Measurement Range40 Hz to 70 Hz
Frequency Measurement Accuracy+/- 0.1 Hz
Undervoltage Dropout50% to 90% of nominal voltage
Undervoltage Pickup(Dropout +2%) to 99% of the nominal system voltage
Underfrequency Dropout Range90 to 97% of the nominal system frequency
Underfrequency Pickup Range(Dropout +1 Hz) to 99% of the nominal system frequency
Overfrequency Dropout Range103 to 110% of the nominal system frequency
Overfrequency Pickup Range101% to (dropout - 1 Hz) of the nominal system frequency
Operating Temperature Range-20 to 70 degree C (-4 to +158 degree F)
Storage Temperature Range-30 to 85 degree C (-22 to +185 degree F)
Operating Humidity0 to 95% relative humidity (noncondensing)
Operating EnvironmentResistant to ammonia, methane, nitrogen,hydrogen and hydrocarbons
Generator Start Relay5A, 1/6 hp @ 250 Vac Vac 5A @ 30 Vdc with a 150W maximum load
K1, K2 Relays
10A, 1-3 hp @ 250 Vac

10A@30 Vdc
Applicable TestingUL-recognized component
Meets intent of UL 991 & UL 1008
Meets IEC 1000-4-2, 1000-4-3, 1000-4-4
Applicable Testing Continued1000-4-5, 1000-4-6, 1000-4-11
CISPR 11, Class A
FCC Part 15, Class A
CSS 22.2-178
Enclosure CompatibilityNEMA 1, NEMA 3R and NEMA 12
UV-resistant ATC-300+ faceplate

  • auxiliary Relay Contacts:
    • source 1 Present 2no And 2nc
    • source 2 Present 2no And 2nc

  • source 1 And Source 2 Sensing:
    • undervoltage / Underfrequency
    • overvoltage / Overfrequency
    • three-phase Rotation Protection
    • three-phase Voltage Unbalance/loss

  • pre-transfer Signal Contacts 1no And 1nc
  • go To Emergency (source 2)
  • seven Field-programmable Time Delays
  • lcd-based Display For Programming, System Diagnostic And Help Message Display
  • mimic Diagram With Source Available And Connected Led Indication
  • time-stamped History Log
  • system Test Pushbutton
  • programmable Plant Exercise (off, Daily, 7,14 And 28 Day) Interval Selectable Run Time 0-600 Minutes No Load/load With Fail-safe
  • integral Overcurrent Protection (optional)
  • in-phase Transition
  • stainless Steel Cover For Controller (optional)
  • communications Via Rs-232 Or Modbus Through An Integrated Rs-485 Port (optional)



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