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SymCom's Model 777-LR-HRG-P2 is a fully programmable electronic overload relay that is designed for resistively grounded systems. The 777-LR-HRG-P2 is recommended for monitoring and protecting any 3-phase 200-480VAC motor, used in a high resistance grounded (HRG) system, drawing 91-800 full load amps (external CTs are required).

SymCom Model 777-LR-HRG-P2 & 777-575-LR-HRG-P2 Electronic Overload Relays Distributors

Model 777-LR-HRG-P2 & 777-575-LR-HRG-P2

Installation Instructions

The units provide unsurpassed protection from faulty voltage and current conditions.

The HRG unit uses an external zero-sequence CT to provide an accurate 1-10A range for ground fault current measurements. When the unit is used in an HRG system, equipment damage can be prevented and system availability can be improved. Pair the 777-LR-HRG-P2 with an appropriate SymCom I/O module to provide independent alarm control. The unit can also be connected to one of SymCom's remote monitors for a simple, cost-effective way to meet new requirements for arc-flash safety.

If you are looking for SymCom 777-LR-HRG-P2 Overload Relays, please call us on (800) 894 - 0412 or email us at we will do our best to help you find the 777-575-LR-HRG-P2 overload relay that you are looking for at the most competitive prices possible. If you are searching for 777-LR-HRG-P2 overload relay technical information (data-sheets) please use the datasheets or product selection guide page links.

The 777-LR-HRG-P2 incorporates 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.


  • Protects high resistance ground 3-phase motors from:
    • High voltage
    • Low voltage
    • Voltage unbalance
    • Reverse-phase
    • Overcurrent
    • Undercurrent
    • Current unbalance
    • Single-phase
    • Ground fault, Class II
  • Ground fault current alarm/trip
  • Network programmable
  • Programmable with 9-volt battery prior to installation
  • Automatic reset with three separate restart delay timers, or manual reset
  • Tamper guard
  • RS-485 communications port (communications module sold separately)
  • 3-digit LED diagnostic display
  • Last fault memory
  • UL and ULC listed
  • CE compliant
  • CSA approved
  • Surface or DIN rail mount
  • 5-year warranty
  • Made in USA

The 777-LR-HRG-P2 can be used as a stand-alone product or used in a network to communicate with a PC, PLC, SCADA system, or SymCom's Solutions Software with the help of its built-in RS-485 communications port. The 777-LR-HRG-P2, in conjunction with SymCom's CIO modules, supports several communication protocols including Modbus/RTU, Modbus/TCP, DeviceNet and Profibus. The units can also be connected to SymCom's remote monitors for a simple, cost-effective way to meet new requirements for arc-flash safety.

The unit's many features include enhanced trip classes beyond the NEMA standard trip classes. The settable trip class range is 2-60, with or without jam protection, and a secondary linear trip delay can be set with a range of 0-60 seconds. If both the trip class and linear trip delay are set, the 777-LR-HRG-P2 will follow the faster trip time. Another feature is the automatic dry-well recovery timer that allows the unit to automatically select a restart delay based on the last cycle's run time. This allows the 777-LR-HRG-P2 to optimize restart delay times.

The 777-LR-HRG-P2 can be pre-programmed with a 9-volt battery prior to actual installation. This can save a lot of time during initial installations and avoid subsequent service calls when commissioning new projects.

Our industrial factory automation supplies distributors warehouse in Boise, Idaho stocks some SymCom products enabling us to further assist you in finding the correct model 777-575-LR-HRG-P2 three-phase relay for your application in the Pacific Northwest USA. We can proudly say that we carry more SymCom/SSAC/Littelfuse in stock than any other SymCom distributors in the Pacific Northwest region. Whether we have model 777-LR-HRG-P2 3-phase overloads in stock in Boise, Idaho or need to get them from SymCom; Clearwater Tech can get 777-575-LR-HRG-P2 electronic overload relay to you fast and save money! It will be very helpful if you have the SymCom 777-LR-HRG-P2 overloads part numbers ready, then our sales representatives can provide you with a pricing and availability quote for 777-575-LR-HRG-P2 overload relays that you are looking for in seconds. If you do not have the part numbers for SymCom 777-LR-HRG-P2 three-phase overloads, our application engineers will be able to help you figure out the part numbers and get the price quote to you as soon as possible.

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RCD's provide ground fault protection to equipment by monitoring the leakage of current to ground. An RCD will trip when a ground fault is detected in excess of the trip rating of the device. An RCD is designed to disconnect a circuit whenever it detects that the electrical current is unbalanced between the phase conductor and the neutral conductor. An imbalance may be caused by phase leaking to ground.

TURCK Modules

The GDP-IS Gateway serves to connect the excom system to PROFIBUS-DP networks. Connection to the PROFIBUS- DP is established via optical fibers or copper cables. When using optical fibers for data transfer an optocoupler pair must be installed between wired and optical PROFIBUS which also adapts the level to the IS layer. When using copper cables a segment coupler (RS485-IS coupler) must be installed to ensure explosion protection.