77C - 77C Series

Series: 77C Series - Single-Phase Current & Voltage Monitor
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The 77C single-phase relay provides motor protection with input voltage from 100–240 V ac and motor full load ampere range as follows: 2–25 A (looped conductors required); 26–90 A (direct); 91–800 A (external CTs required).

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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) 100 - 240 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 (looped conductors required); 26 - 90 (direct); 91 - 800 (external CTs required)
Timing Accuracy (%) 5% ±1 s
Rapid Cycle Timer (s) 0; 2 - 500 s
Restart Delay Range After Under/Overcurrent: 2 - 500 m/s; # of Restarts: Overcurrent: 0; 1; oc1; 2; oc2; 3; oc3; 4; oc4; A (Automatic); OCA; Undercurrent: 0; 1; 2; 3; 4; A (Automatic)
Repeat Accuracy (%) Voltage: ±0.5% of nominal voltage; Current: ±1% (direct; no external CTs)
Overvoltage Trip Voltage (%) 85V - HV setting
Undervoltage Trip Voltage LV setting - 264 V
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; or lin (linear)
Undercurrent Trip Point 0; 10 - 98 A … MULT or 40 - 100% of CT primary
Undercurrent Trip Delay (s) 2 - 60 s
Current Accuracy (%) ±3% (<100 A direct)
Ground Fault Accuracy (%) ±15%
Sensor Hole Size Max conductor size: 0.65 in (with insulation)
Short Circuit (kA) UL: 100; CSA: 10
Surge Protection IEC: 61000-4-5 Level 3 2 kV line-to-line; Level 4 4 kV line-to-ground
Protection Class IP20; NEMA 1 (finger safe)
Pollution Degree 3
CT Ratio 1 - 10; or 100 - 800 ratio
Address A01 - A99
Termination Type 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
Check Stock Yes

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