SEL-351S Protection and Breaker Control Relay

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

SEL-351S

Protection and Breaker Control Relay

The SEL-351S Relay enhances your quality of service through lowered costs and expanded operator controls for integrated protection, monitoring, and control schemes.

Dependable Overcurrent Protection
Sensitive, secure combination of phase, negative-sequence, residual-ground, and neutral-ground overcurrent elements, including directional control, and programmable US and IEC time-current curves for complete distribution system protection.
Innovative Directional Element Polarization
Positive-sequence voltage-polarized phase directional element with memory for directional stability during phase faults.

Best Choice Ground Directional Element& System logic for secure ground directional element operation for all types of system grounding practices under varying system conditions.
Large Operator Controls
Large front-panel keyboard with local display panel and programmable operator control interface pushbuttons to replace unnecessary control switches and wiring at the breaker control panel.
Trip/Close pushbuttons and indicating lamps
Optional Trip/Close pushbuttons with arc suppression and indication lamps are independently operated and remain functional even if the relay is out of service. Switch contacts and indicating lamps are separately wired to screw terminal blocks on the rear of the relay. Choose the wiring arrangement that best suits your need for breaker control and status indication.
Under- / Overfrequency Protection
Six levels of frequency elements, plus under- / overvoltage protection for advanced load shedding.
Communications
Optional MIRRORED BITS^® communications for pilot protection schemes and remote relay-to-relay I/O functions.
Reclosing Control
Four-shot recloser with sequence coordination, synchronism check, and voltage check.
Recloser time-overcurrent curves
Use any of the 38 traditional recloser curves in the SEL-351S Relay to time coordinate with downstream circuit reclosers. Sequence coordination keeps the SEL-351S in step with downstream reclosers and prevents tripping by overreaching overcurrent elements for faults beyond reclosers. Five each standard US and IEC time-overcurrent curves provide coordination with other time-overcurrent relays.
Fault Locator
Impedance based fault locator for accurate distance to fault measurements.
Metering, PQ Monitoring
Accurate metering eliminates the need for external meters (MW, MVAR, MWHr, MVARHr, PF, instantaneous/peak demand). Optional power quality monitoring records voltage sags, swells, and interruptions.
Input Voltage Settings
Select line-neutral (WYE) or line-line (delta) input AC voltage connections using software setting.
ACSELERATOR^® Software
Helps speed relay application by allowing you to develop relay settings off-line, program SELOGIC^® control equations, and analyze post-fault event reports.

Breaker trip/close control switches and indicating lamps

Eliminate Panel-Mounted Breaker Control Switches

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Connectorized hardware configuration.
MIRRORED BITS communications and load profiling.
Additional inputs and standard or high-current interrupting contact outputs.
Low range neutral current input channel for non-directional Sensitive Earth Fault (SEF) applications.
Low range neutral current channel for directional control for Petersen Coil grounded, high-impedance grounded, or ungrounded power systems.
Distributed Network Protocol (DNP) 3 Level 2 Slave communications protocol.
Power elements, voltage sag, swell, interruption records.
User-configurable labels for operator controls and target LEDs.
Pushbutton guard kit to increase security of breaker trip/close pushbuttons
Conformal Coating—Protect equipment from harsh environments and airborne contaminants such as hydrogen sulfide, chlorine, salt, and moisture.
Learn more about conformal coating.

Replace older electromechanical relay schemes, control switches, and metering devices in outdoor breaker control enclosures.
Commission automatic substation restoration schemes using programmable user interface controls and MIRRORED BITS communications.
Use the programmable control logic and integration features with a communication link for control and protection of remote substations.
Selectively coordinate with downstream SEL-351R Recloser Controls (applied on circuit reclosers) using a MIRRORED BITS communications link for secure, high-speed fault clearing on distribution circuits and industrial co-generation facilities.
Send synchrophasor data to SCADA and wide-area measurement systems using SEL FastMessages at rates of up to 60 times per minute. Accuracy of ± 1 degree and microsecond timing of event reports improve system visualization and event analysis. Use SEL-5077 SYNCHROWAVE^® Server Software to time-correlate synchrophasor data from SEL-351S Relays and send it to display and archiving systems, such as SEL-5078 SYNCHROWAVE Console Software.
Dispatch line crews to quickly isolate overhead line problems, and restore service faster using built-in fault locator, as compared to patrolling the line.
Schedule circuit breaker maintenance based on need, as determined from breaker monitoring data and alarms.
Analyze overcurrent protection system performance using built-in sequential events recorder.
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 send and retrieve settings, 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-351 relays.

Budgetary Retail, Quantity 1: $3,045
Fully Optioned Price: $5,275
(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.)