American SEL-387 protection device with differential current and overcurrent relay
LEHIY item code: LH-SEL-0019
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SEL-387 Current Differential and Overcurrent Relay (USA) - We can provide remote or on-site installation and commissioning services for SEL products from the USA. We source directly from the US SEL factory, ensuring genuine products, and offer competitive pricing through group shipping.
The SEL-387 Current Differential and Overcurrent Relay provides protection, control, and metering for transformers, busbars, circuit breakers, and feeders.
Features include four three-phase current inputs with independent constrained and unconstrained differential protection, programmable single-slope or dual-slope differential characteristics, circuit breaker monitor, battery voltage monitor, and enhanced SELogic control equations.
The SEL-387 Current Differential and Overcurrent Relay features include: 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 Current Differential and Overcurrent Relay 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. Provides backup distribution bus or feeder protection using low-side overcurrent elements.
Independent winding overcurrent protection—provides comprehensive overcurrent protection for each winding input via torque-controlled overcurrent elements. In the SEL-387, combined current characteristics sum the currents of two current transformers (CTs) for overcurrent applications involving a ring bus and a half-circuit breaker.
Condition-based maintenance—optional thermal monitoring activates control operations or issues alarms when the transformer is at risk of excessive insulation aging or loss of life. Uses shoot-through fault monitoring to collect accumulated shoot-through fault data and schedule proactive maintenance.
Our company offers a superior supply of SEL-387 protection devices with current differential and overcurrent relays, sourced directly from the manufacturer, guaranteeing genuine products.
The SEL-387 protection device product overview is as follows: Two-winding, three-winding, and four-winding current differential protection with programmable single-slope or dual-slope percentage constraints.
Sensitive current differential protection is monitored by selected second and fourth harmonic blocking or suppression elements, as well as fifth harmonic and DC blocking elements for safety protection of up to four windings. Phase current harmonic blocking is set to a common or independent winding basis.
Unconstrained high-level differential elements provide fast operation for high-amplitude internal faults. "All-weather" phase angle compensation setting and automatic tap calculation simplify setup.
Independent winding overcurrent protection with torque-controlled overcurrent elements, including one instantaneous, one definite-time, and one inverse-time element, each for phase current, negative-sequence current, and zero-sequence ground current, providing comprehensive overcurrent protection for each winding input.
Combined current function adds currents from two CTs for ring bus and one-half-circuit breaker overcurrent applications. Shot-through fault logging and monitoring: Shot-through fault loads are logged and accumulated for SELogic control equations or manual monitoring.
Protection and control logic is used for restricted ground fault (REF) logic in sensitive grounding star winding ground fault protection. bits, and remote control elements are used to customize advanced protection and control schemes.
Local programmable control elements and programmable text display points are provided for an advanced local operator interface. Metering and reporting include oscilloscope event reporting (up to 7 60-cycle reports), Sequential Event Recorder (SER) reporting, and accurate metering, eliminating or reducing external recorder and metering requirements.
Substation battery voltage monitors and circuit breaker contact wear monitors provide critical data for reliability-centered maintenance (RCM) programs. The acSELerator QuickSet SEL-5030 software allows offline development of relay settings, programming of SELogic control equations, and analysis of post-fault event reports.
For details on the SEL-387 protection device, please contact our sales department.
Plain language sourcing guide for American SEL-387 protection device with differential current and overcurrent relay
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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-387 protection device with differential current and overcurrent relay
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