777-TS - 777 Series

Series: 777
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The 777 is a fully programmable electronic overload relay designed to protect any motor drawing 2-800 full load amps (external CTs are required above 90 amps). The 777 (family of products) is for 3-phase 200-480VAC applications, with several specialized units for other voltage ranges and unique applications. Common applications include conveyor systems, HVAC equipment, saws and grinders, fan motors, and almost any pumping application. Some unique applications include use with a Subtrol® equipped Franklin submersible motor to detect high motor temperatures and applications where a fast linear trip is required.

All of the overload relays provide unsurpassed protection by combining overload, voltage, phase loss and reversal, voltage and current unbalance, power monitoring, and underload based on current in one package. For standalone applications, the units incorporate a 3-digit LED display that is used for programming, providing real-time operational information and displaying diagnostic codes to aid in troubleshooting a fault condition. The units also feature a communications port that can be used with communication modules listed in the 777 accessories section to form a Modbus, DeviceNet™, Profibus, or Ethernet network. Up to 99 units can be remotely monitored and controlled from a PC, PLC, or SCADA system, and data logging through a PC with the optional Solutions software. This capability allows for a simple, cost-effective way to meet new requirements for arc-flash safety.

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Product Literature

For Technical Questions

Call +1 800-832-3873 or email us at relays@littelfuse.com 

Property (Mouseover for details) Value
Input Voltage (V) 200 - 480 Vac
Maximum Input Power 10
Input AC Line Frequency (Hz) 50 / 60
Output Form SPDT - Form C
Output Load Rating (VA) Pilot Duty: 480 VA @ 240 Vac B300; General Purpose: 10 A @ 240 Vac
Full Load Amp Range (A) 2 - 25: 3 phase (looped conductors required); 25 - 90: 3 phase (direct); 80 - 800: 3 phase (external CTs)
Timing Accuracy (%) 5% ±1 s
Rapid Cycle Timer (s) 0; 2 - 500 s
Restart Delay Range All faults: 2 - 500 m; # of Restarts: All faults except undercurrent: 0; 1; oc1; 2; oc2; 3; oc3; 4; oc4; A; ocA (Automatic); Undercurrent: 0; 1; 2; 3; 4; A (Automatic)
Repeat Accuracy (%) Voltage: ±0.5% of nominal voltage; Current: ±1% (<100 A direct)
Overvoltage Trip Voltage (%) LV setting - 528 V
Undervoltage Trip Voltage 170 V - HV setting
Voltage Unbalance Trip Point (%) 2 - 15% or 999
Voltage Accuracy (%) ±1%
Overcurrent Trip Point (20 - 100 A) … MULT of 80 - 120% of CT primary
Overcurrent Trip Class 5; J5; 10; J10; 15; J15; 20; J20; 30; J30
Undercurrent Trip Point 0; 10 - 98 A … MULT or 40 - 140% of CT primary
Undercurrent Trip Delay (s) 2 - 60 s
Current Unbalance Trip Point (%) 2 - 25% or 999 (disabled)
Current Unbalance Trip Delay (s) % over setpoint / Trip time: 1% / 30s; 2% / 15s; 3% / 10s; 4% / 7.5s; 5% / 6s; 6% / 5s; 10% / 3s; 15% / 2s
Current Accuracy (%) ±3% (<100 A direct)
Ground Fault Current Trip Point (A) (3 - 20) … MULT or 10 - 30% of primary CT or OFF
Ground Fault Trip Delay (s) % of setpoint / Trip time: 101 - 200% / 8s ± 1s; 30s; 201 - 300% / 4s ± 1s; 301 - 400% / 3s ± 1s; 401%+ / 2s ± 1s
Ground Fault Accuracy (%) ±15%
Sensor Hole Size Max conductor size: 0.65 in (with insulation)
Short Circuit (kA) 100
Surge Protection IEC: 61000-4-5 Level 3 2 kV line-to-line; Level 4 4 kV line-to-ground
Protection Class IP20 (finger safe)
Pollution Degree 3
CT Ratio 1 - 10; or 100 - 800 ratio
Address A01 - A99
Termination Type Torque: 7 in-lbs
Mounting Method Surface mount (4 - #8 screws) or DIN rail mount
Operating Temperature -20° to 70°C (-4° to 158°F)
Storage Temperature (F/C) -40° to 80°C (-40° to 176°F)
Humidity 10 - 95% non-condensing per IEC 68-2-3
Dimensions 3.05 H x 3.85 W x 5.05 D in. (77.5 x 97.8 x 128.3 mm)
Weight (lbs/g) 0 Kg
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