SEL-387E Current Differential and Voltage Relay

Products for Protection, Monitoring, Control, Automation, and Metering

SEL-387E

Current Differential and Voltage Relay

Use the SEL-387E Relay to provide comprehensive protection, metering, monitoring, and automation for important transformers, reactors, and other power apparatus.

Two- and Three-Winding Current Differential Protection
Sensitive current differential protection with programmable single- or dual-slope percentage restraint, supervised by a choice of second- and fourth-harmonic blocking or restraint elements, plus fifth-harmonic and dc blocking elements for secure protection of up to three windings. Phase current harmonic blocking is set for either common or independent winding basis. Unrestrained high-set differential elements provide fast operation for high-magnitude internal faults. "Around the clock" phase angle compensation settings and automatic tap calculations simplify settings.
Individual Winding Overcurrent Protection
Torque-controllable overcurrent elements, including one instantaneous, one definite-time, and one inverse-time element each for phase, negative-sequence, and residual ground currents provide comprehensive overcurrent protection on each winding input. Combined overcurrent feature sums current from two inputs for ring bus and breaker-and-a-half overcurrent applications.
Through-Fault Recording and Monitoring
Through-fault duty is recorded and accumulated for use in SELOGIC^® control equations or manual monitoring.
Overexcitation (V/Hz) Protection
Volts-per-hertz elements detect overexcitation conditions in the protected apparatus. Choose from multiple curves (including user-defined) and definite-time elements for alarm and tripping applications.
Under- / Overfrequency Protection
There are six available frequency elements. The user sets the desired number of frequency elements.
Restricted Earth Fault
Restricted Earth Fault (REF) logic for sensitive protection of grounded wye windings.
Control Logic
SELOGIC control equations with SELOGIC variables, timers, latch bits, and remote control elements for customizing advanced protection and control schemes. Local programmable control elements and programmable text display points for advanced local operator interface.
Metering and Reporting
Oscillographic event reports (up to seven 60-cycle reports), Sequential Events Recorder (SER) reporting, and accurate three-phase power metering eliminate or reduce external recorder and metering requirements. Station battery monitor and circuit breaker contact wear monitor provide important data for Reliability Centered Maintenance (RCM) programs.
Communications
EIA-232 and EIA-485 serial ports for local/remote access and system integration.

Download event reports using the optional Ethernet port. Quickly move information with IEC 61850 protocol.
ACSELERATOR^® QuickSet™ Software
Develop relay settings off-line, program SELOGIC control equations, and analyze post-fault event reports.

Rack-mount or panel-mount hardware.
Additional contact inputs and standard or high-current interrupting output contacts.
Connectorized^® packaging (includes additional contact inputs and output contacts).
Additional local and remote control elements and binary SER messaging.
Distributed Network Protocol (DNP) 3 Level 2 Slave communications protocol.
Conformal Coating—Protect equipment from harsh environments and airborne contaminants such as hydrogen sulfide, chlorine, salt, and moisture.
Learn more about conformal coating.

Protect any two- or three-winding power transformer.
Protect reactors, generators, large motors, and other multi-terminal power apparatus.
Apply with any combination of delta- or wye-connected CT and PT secondary circuits.
Perform predictive maintenance based on accumulated through-fault duty as compared to transformer capability as defined in ANSI Standard C57.109. Use recorded fault values or an alarm set point to initiate an evaluation of transformer maintenance needs.
Use built-in winding overcurrent elements for backup protection.
Use one or more of the six available frequency elements for load shedding and/or load restoration schemes.
Reduce or eliminate the need for panel-mounted metering devices by utilizing the accurate three-phase power and energy metering capabilities of the relay.
Use SELOGIC Control Equations to create breaker failure logic.
Detect ground faults through delta-wye transformer banks, or provide sensitive phase-to-phase protection, independent of load current, with negative-sequence overcurrent element.
Use low-side overcurrent elements for backup distribution bus or feeder protection.
Use SEL-5040 Power System Report Manager Software to automatically gather relay event reports on your PC and manage them with a database.
Use SEL-5010 Relay Assistant Software to manage your relay settings.
Use SEL-5601 Analytic Assistant Software to display oscillograms and vector diagrams to analyze event reports.

SEL provides options to help you efficiently and safely commission and test these relays.
	Streamline commissioning by using the SEL-4391 Data Courier™ to gather event reports and install enhancements.
	When access to the back of panels and cabinets is allowed, use a Connectorized^® version of this relay for fast installation and testing.
	Improve safety, save time, and reduce costs with SEL-4600 Series Test Blocks and Plugs. Use the SEL recommended standard block and plug configurations for SEL-387E relays.

Budgetary Retail, Quantity 1: $5,780
Fully Optioned Price: $8,753
(Prices displayed are for planning purposes and are subject to change. Contact your SEL sales representative today for a quote on configurations and quantities to meet your needs.)