{"product_id":"abb-relion-rej603-self-powered-feeder-protection-relay-overcurrent-earth-fault-protection","title":"ABB Relion REJ603 Self-Powered Feeder Protection Relay | Overcurrent \u0026 Earth-fault Protection","description":"\u003ch4\u003eOverview:\u003c\/h4\u003e\n\u003cp\u003eThe\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eABB Relion REJ603\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eis a self-powered protection relay designed for secondary distribution networks, where access to an auxiliary power source may be unavailable. It is primarily used in\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eRing Main Units (RMUs)\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eand compact switchgear, offering reliable overcurrent and earth-fault protection. Powered by\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eCurrent Transformers (CTs)\u003c\/strong\u003e, the REJ603 ensures protection even when external power is absent, making it an ideal solution for remote locations and installations with limited power supply.\u003c\/p\u003e\n\u003ch4\u003eKey Features:\u003c\/h4\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eSelf-Powered Operation\u003c\/strong\u003e: The\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eREJ603\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003egenerates the necessary operating energy from the primary circuit’s current transformers (CTs). It ensures protection during fault conditions, even at startup (cold start).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eProtection Functions\u003c\/strong\u003e:\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eThree-Phase Overcurrent Protection\u003c\/strong\u003e: Covers both low-set (I\u0026gt;) and high-set (I\u0026gt;\u0026gt;) overcurrent protection stages, providing selective coordination and fast response to faults.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eEarth Fault Protection\u003c\/strong\u003e: Detects leakage currents to ground with both phase current summation and optional use of a core balance CT (CBCT).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eCurrent Transformer Compatibility\u003c\/strong\u003e: The relay is optimized for dual-core CTs that have two windings—one for measurement and protection, and one for energy harvesting to power the relay.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eMeasurement and Monitoring\u003c\/strong\u003e:\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003eMonitors phase currents and earth current for a comprehensive fault analysis.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eUser Interface\u003c\/strong\u003e:\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eLCD Display\u003c\/strong\u003e: Shows fault information and operational status.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eLED Indicators\u003c\/strong\u003e: Provides visual feedback for fault types (overcurrent, earth-fault).\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eCommunication Options\u003c\/strong\u003e:\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eModbus RTU (RS-485)\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003efor remote monitoring.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eOptical Port\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003efor local communication.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eEnvironmentally Robust\u003c\/strong\u003e: The\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eREJ603\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eoperates in temperatures ranging from\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003e-25°C to +70°C\u003c\/strong\u003e, ensuring reliability in a variety of environments.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eTechnical Specifications:\u003c\/h4\u003e\n\u003ctable class=\"w-fit min-w-(--thread-content-width)\"\u003e\n\u003cthead\u003e\n\u003ctr class=\"firstRow\"\u003e\n\u003cth\u003e\u003cstrong\u003eFeature\u003c\/strong\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cstrong\u003eSpecification\u003c\/strong\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePower Supply\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eSelf-powered via CTs (optional auxiliary power)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eProtection Functions\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eOvercurrent (I\u0026gt;, I\u0026gt;\u0026gt;), Earth-fault (Io)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eMeasurement\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003ePhase currents, Earth current\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTrip Output\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eLow-energy trip coil (powered by relay)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCommunication\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eModbus RTU (RS-485), Optical Port\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTemperature Range\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e-25°C to +70°C\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDisplay\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eLCD with push-buttons, LED indicators\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003ch4\u003eVariants:\u003c\/h4\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eVersion 1.5\u003c\/strong\u003e: Standard for basic RMU applications.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eVersion 3.0\u003c\/strong\u003e: Enhanced version with better communication protocols and upgraded hardware interfaces.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eApplications:\u003c\/h4\u003e\n\u003cul class=\"list-paddingleft-2\"\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eSecondary Substations\u003c\/strong\u003e: Protects transformers and feeders in secondary distribution networks.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eRemote Sites\u003c\/strong\u003e: Ideal for areas without a stable DC power supply or UPS.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eRetrofits\u003c\/strong\u003e: Replaces older mechanical or thermal relays in existing switchgear, upgrading the protection system with modern features.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eFrequently Asked Questions (FAQ):\u003c\/h4\u003e\n\u003cp\u003e\u003cstrong\u003eQ1: What is the main advantage of the self-powered feature of the REJ603?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eREJ603\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eeliminates the need for an external power supply, drawing energy directly from the current transformers (CTs), ensuring continuous protection even if the external power fails.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ2: Can the REJ603 be used in remote locations without auxiliary power?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eYes, the self-powered design makes the\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eREJ603\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eideal for remote sites where stable DC battery systems are not available.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ3: How does the Earth-fault protection work in the REJ603?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe\u003cspan\u003e \u003c\/span\u003e\u003cstrong\u003eREJ603\u003c\/strong\u003e\u003cspan\u003e \u003c\/span\u003eutilizes phase current summation or can integrate with a core balance CT (CBCT) for accurate detection of leakage currents to ground, ensuring reliable earth-fault protection.\u003c\/p\u003e","brand":"ABB","offers":[{"title":"Default Title","offer_id":44088065785955,"sku":"REJ603","price":180.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0549\/2775\/3315\/files\/REJ603.jpg?v=1774840167","url":"https:\/\/precisemodule.com\/products\/abb-relion-rej603-self-powered-feeder-protection-relay-overcurrent-earth-fault-protection","provider":"Precise Module Ltd.","version":"1.0","type":"link"}