77C Series - Single-Phase Current & Voltage Monitor

Series: 77C
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Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation, automotive, military, aerospace, medical, life-saving, life-sustaining or nuclear facility applications, devices intended for surgical implant into the body, or any other application in which the failure or lack of desired operation of the product may result in personal injury, death, or property damage) other than those expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for any purpose not expressly set forth in applicable Littelfuse documentation. Littelfuse shall not be liable for any claims or damages arising out of products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse documentation. The sale and use of Littelfuse products is subject to Littelfuse Terms and Conditions of Sale, unless otherwise agreed by Littelfuse. "Littelfuse" includes Littelfuse, Inc., and all of its affiliate entities.

The 777/ 77C 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-HVR-SP and 77C (family of products) are for single-phase 100-240VAC applications. Common applications include conveyor systems, HVAC equipment, saws and grinders, fan motors, and almost any pumping application.

All of the overload relays provide unsurpassed protection by combining overload, underload, and voltage 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.

Product Literature

For Technical Questions

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

Access specifications, certifications, check availability and order parts below

Catalog #Input
Voltage (V)		Output
Form		Termination TypeMounting MethodFull Load Amp Range (A)DimensionsWeight (lbs/g)Overcurrent Trip ClassOvercurrent Trip PointAddressCurrent Accuracy (%)Ground Fault Accuracy (%)HumidityInput AC Line Frequency (Hz)Maximum Input PowerStockSamplesCompare
777-HVR-SP340 - 480 VacSPDT - Form CTorque: 7 in-lbsSurface mount (4 - #8 screws) or DIN rail mount2 - 25 (looped conductors required); 26 - 90 (direct); 80 - 800 (external CTs required)3.05 H x 3.85 W x 5.05 D in. (77.5 x 97.8 x 128.3 mm)0 Kg5; J5; 10; J10; 15; J15; 20; J20; 30; J30; or lin (linear)(20 - 100 A) … MULT of 80 - 120% of CT primaryA01 - A99±3% (<100 A direct)±15%10 - 95% non-condensing per IEC 68-2-350 / 6010CheckOrder
77C100 - 240 VacSPDT - Form C7 in.-lbs.Surface mount (4 - #8 screws) or DIN rail mount2 - 25 (looped conductors required); 26 - 90 (direct); 91 - 800 (external CTs required)3.05 H x 3.85 W x 5.05 D in. (77.5 x 97.8 x 128.3 mm)0 Kg5; J5; 10; J10; 15; J15; 20; J20; 30; J30; or lin (linear)(20 - 100 A) … MULT of 80 - 120% of CT primaryA01 - A99±3% (<100 A direct)±15%10 - 95% non-condensing per IEC 68-2-350 / 6010CheckOrder
77C-LR100 - 240 VacSPDT - Form C7 in.-lbs.Surface mount (4 - #8 screws) or DIN rail mount1.0 - 2.5 (looped conductors required); 2.0 - 9.0 (direct)3.05 H x 3.85 W x 5.05 D in. (77.5 x 97.8 x 128.3 mm)0 Kg5; J5; 10; J10; 15; J15; 20; J20; 30; J30; or lin (linear)(20 - 100 A) … MULT of 80 - 120% of CT primaryA01 - A99±3% (<100 A direct)±15%10 - 95% non-condensing per IEC 68-2-350 / 6010CheckOrder
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