{"product_id":"st570b3-motor-protection-controller","title":"ST570B3 Motor Protection Controller","description":"\u003ch2\u003eProduct Overview\u003c\/h2\u003e\u003cp\u003eThe ST570B3 Motor Protection Controller is designed for low-voltage motor applications rated at 50\/60Hz and up to AC380V\/AC400V. It integrates protection, measurement, control, management, and communication functions. Working in conjunction with contactors, soft starters, variable frequency drives, and circuit breakers, it enables multiple motor starting and control schemes to ensure safe motor operation. It is the ideal choice as a terminal unit for intelligent MCC or production DCS systems.\u003c\/p\u003e\u003cp\u003eThe series adopts a modular design, consisting of a main body and dedicated current transformers. It is compact, easy to install, and suitable for direct installation in 1\/4 modular and larger drawer cabinets.\u003c\/p\u003e\u003cp\u003eWidely applicable in power generation, petroleum, petrochemical, chemical, metallurgy, coal, paper, rail transit, and other industries.\u003c\/p\u003e\u003cp\u003eComplies with GB\/T 14048.4 (Low-voltage switchgear and controlgear – AC contactors and motor starters) and GB\/T 14598.303 (General technical requirements for digital comprehensive motor protection devices).\u003c\/p\u003e\u003ch2\u003eTechnical Specifications\u003c\/h2\u003e\u003ch3\u003e2.1 Environmental Conditions\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eOperating Temperature: -10 to +55°C\u003c\/li\u003e\n\u003cli\u003eStorage Temperature: -25 to +70°C\u003c\/li\u003e\n\u003cli\u003eRelative Humidity: 5–95% (no condensation or icing)\u003c\/li\u003e\n\u003cli\u003eAtmospheric Pressure: 80–106 kPa\u003c\/li\u003e\n\u003cli\u003eAltitude: \u0026lt;3000 m\u003c\/li\u003e\n\u003cli\u003ePollution Degree: Level 3\u003c\/li\u003e\n\u003cli\u003eProtection Degree: IP20\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003e2.2 Rated Parameters\u003c\/h3\u003e\u003ch4\u003eAuxiliary Power Supply\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003ePower Range: 85–264 VAC \/ 90–300 VDC\u003c\/li\u003e\n\u003cli\u003ePower Consumption: \u0026lt;5W\/10VA, Inrush Current 20A\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eElectromagnetic Compatibility (EMC)\u003c\/h3\u003e\u003ctable\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eNo.\u003c\/th\u003e\n\u003cth\u003eTest Item\u003c\/th\u003e\n\u003cth\u003eStandard\u003c\/th\u003e\n\u003cth\u003eLevel\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e1\u003c\/td\u003e\n\u003ctd\u003eRadiated Emission Limits\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003ePass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e2\u003c\/td\u003e\n\u003ctd\u003eConducted Emission Limits\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003ePass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e3\u003c\/td\u003e\n\u003ctd\u003eRF Electromagnetic Field Radiated Immunity\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003e10 V\/m\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e4\u003c\/td\u003e\n\u003ctd\u003eElectrostatic Discharge Immunity\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003eLevel IV\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e5\u003c\/td\u003e\n\u003ctd\u003eConducted Disturbance Induced by RF Fields\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003e10 V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e6\u003c\/td\u003e\n\u003ctd\u003eElectrical Fast Transient\/Burst Immunity\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003eClass A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e7\u003c\/td\u003e\n\u003ctd\u003eDamped Oscillatory Wave Immunity (1MHz \u0026amp; 100kHz)\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003eLevel 3\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e8\u003c\/td\u003e\n\u003ctd\u003eSurge Immunity\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003eClass A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e9\u003c\/td\u003e\n\u003ctd\u003ePower Frequency Immunity\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003eClass A\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e10\u003c\/td\u003e\n\u003ctd\u003ePower Frequency Magnetic Field Immunity\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003eLevel 5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e11\u003c\/td\u003e\n\u003ctd\u003ePulse Magnetic Field Immunity\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003eLevel 5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e12\u003c\/td\u003e\n\u003ctd\u003eDamped Oscillatory Magnetic Field Immunity\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003eLevel 5\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e13\u003c\/td\u003e\n\u003ctd\u003eAC\/DC Voltage Dips\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003ePass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e14\u003c\/td\u003e\n\u003ctd\u003eAC\/DC Voltage Interruptions\u003c\/td\u003e\n\u003ctd\u003eGB\/T 14598.26\u003c\/td\u003e\n\u003ctd\u003ePass\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch2\u003eProtection Functions\u003c\/h2\u003e\u003ch3\u003eThermal Overload Protection\u003c\/h3\u003e\u003cp\u003ePrevents motor damage from overload heating. Uses equivalent current vs. rated current ratio as the criterion, considering both positive and negative sequence thermal effects. Supports automatic and manual reset modes.\u003c\/p\u003e\u003ch3\u003eBlocking Protection\u003c\/h3\u003e\u003cp\u003eProtects against rotor stall during operation. Activates when the maximum phase current exceeds the set value, executing in definite-time mode.\u003c\/p\u003e\u003ch3\u003etE Time Protection\u003c\/h3\u003e\u003cp\u003eApplicable to increased-safety explosion-proof motors under continuous operation. Complies with GB3836.3. The tE trip time must satisfy tETrip ≤ tE.\u003c\/p\u003e\u003ch3\u003eStart Timeout Protection\u003c\/h3\u003e\u003cp\u003ePrevents insulation damage from excessive start time. Activates if current exceeds the set value after the configured start timeout period.\u003c\/p\u003e\u003ch3\u003eSingle-Phase Ground Protection\u003c\/h3\u003e\u003cp\u003eCalculates ground current from the vector sum of three-phase currents. Effective in TN distribution systems for detecting single-phase ground faults without an external ground CT.\u003c\/p\u003e\u003ch3\u003eLeakage Protection\u003c\/h3\u003e\u003cp\u003eDetects insulation degradation or non-direct ground faults. Requires an external zero-sequence CT. Executes in definite-time mode.\u003c\/p\u003e\u003ch3\u003ePhase Loss Protection\u003c\/h3\u003e\u003cp\u003eActivates when the maximum current unbalance exceeds 80% after motor start.\u003c\/p\u003e\u003ch3\u003eCurrent Unbalance Protection\u003c\/h3\u003e\u003cp\u003eActivates when the maximum current unbalance exceeds the set value and average current is above 25%.\u003c\/p\u003e\u003ch3\u003eReverse Phase Sequence Protection\u003c\/h3\u003e\u003cp\u003eActivates 200ms after detecting incorrect three-phase current sequence.\u003c\/p\u003e\u003ch3\u003eUnderload Protection\u003c\/h3\u003e\u003cp\u003eDetects abnormal low-load conditions such as pump cavitation, fan airflow loss, or conveyor belt breakage. Executes in definite-time mode based on current or power.\u003c\/p\u003e","brand":"Wan Long Electric","offers":[{"title":"Default Title","offer_id":44272808067138,"sku":"ST570B3","price":280.0,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0688\/1221\/0242\/files\/ST570B3-1.webp?v=1784524342","url":"https:\/\/wanlongelectric.com\/products\/st570b3-motor-protection-controller","provider":"Wan Long Electric Group Co., Ltd.","version":"1.0","type":"link"}