American SEL-387A protection device features a differential current overcurrent relay.
LEHIY item code: LH-SEL-0016
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The SEL-387A Current Differential and Overcurrent Relay is a US-made SEL product sourced directly from the manufacturer, ensuring authenticity and competitive pricing. We offer remote or on-site installation and commissioning services for SEL products. The SEL-387A provides constrained and unconstrained differential protection for two terminals.
Second, fourth, and fifth harmonic elements enhanced with DC components provide safety under transformer energized and over-excited conditions with user-defined harmonic suppression or blockout selection. Overcurrent elements provide backup protection, contributing to the SEL-387A's versatility.
Multi-winding current differential protection—protects power transformers with up to four windings by combining single-slope or dual-slope percentage differential characteristics, overcurrent protection, and limiting ground fault (REF) protection. The SEL-387A is a low-cost solution for protecting two-winding transformers.
Beyond typical transformer protection—protects reactors, generators, large motors, and other multi-terminal electrical equipment. Low-side overcurrent protection provides backup distribution bus or feeder protection. Independent winding overcurrent protection—provides comprehensive overcurrent protection for each winding input via torque-controlled overcurrent elements.
Condition-based maintenance—optional thermal monitoring activates control actions or issues alarms when the transformer is at risk of excessive insulation aging or loss of life. Shot-through fault monitoring collects accumulated shot-through fault data and schedules proactive maintenance.
Our company offers the American SEL-387A protection device current differential overcurrent relay, sourced directly from the manufacturer, guaranteeing authenticity.
The dual-winding current differential protection SEL-387A provides sensitive current differential protection with programmable single-slope or dual-slope percentage limits, monitored by selectable second and fourth harmonic blocking or suppression elements, as well as fifth harmonic and DC blocking elements for safe protection of up to two windings.
Phase current harmonic blocking is set to common or independent winding basis. Unconstrained high-level differential elements provide rapid operation for high-amplitude internal faults. "All-weather" phase angle compensation setting and automatic tap calculation simplify setup.
Independent winding overcurrent protection features torque-controlled overcurrent elements, including an instantaneous, a definite-time, and an inverse-time element. Each element is used for phase current, negative-sequence current, and zero-sequence ground fault current, providing comprehensive overcurrent protection for each winding input.
Shot-through fault logging and monitoring: Shot-through fault loads are logged and accumulated for use in SELogic control equations or manual monitoring. Protection and control logic: Limiting ground fault (REF) logic provides sensitive protection against ground faults in star windings.
SELogic control equations with SELogic variables, timers, latch bits, and remote control elements are used to customize advanced protection and control elements. Local programmable control elements and programmable text display points provide a superior local operator interface.
Metering and reporting: Oscilloscope event reporting (up to 7 60-cycle reports), Sequential Event Recorder (SER) reporting, and accurate metering eliminate or reduce external recorder and metering requirements. Substation battery voltage monitors and circuit breaker contact wear monitors provide critical data for reliability-centric maintenance (RCM) programs.
When used with the SEL-2600A RTD module, it can measure the temperature of up to 24 RTDs. The acSELerator QuickSet software allows offline development of relay settings, programming of SELogic control equations, and analysis of post-fault event reports.
For details on the SEL-387A relay protection device, please contact our sales department.
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| Brand Name: | SEL | Certification: | ISO9001, CE |
|---|---|---|---|
| Place of Origin: | China | Condition: | New |
| Warranty: | 1 year | Customized sourcing: | available |
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American SEL-387A protection device features a differential current overcurrent relay.
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