SEL-311L Line Current Differential Protection and Automation System

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

SEL-311L

Line Current Differential Protection and Automation System

Protect Lines With Easy-to-Use Current Differential Relays

Secure Line Differential Protection
Sensitive differential elements provide sub-cycle operating time. Restraint for external faults uses an easy-to-set vector ratio of remote and local currents.
Synchrophasor Measurements
Turn state estimation into state measurement with wide-area measurement of voltage and current phase angles and magnitudes. Improve system stability with high-speed, load-angle measurements. Increase stable loading with analysis of voltage and angular stability.
Complete Line Protection
Protect transmission lines using differential and a combination of four stepped-distance zones of phase and ground-distance elements in communications-assisted schemes, with directional overcurrent element backup protection. Patented Capacitance Voltage Transformer (CVT) transient overreach logic enhances security of Zone 1 distance elements. Best Choice Ground Directional Element™ logic optimizes directional element performance and requires no directional settings.
Single-Pole Tripping
Use the optional single-pole tripping capability of the differential elements to improve system stability.
Monitoring and Metering
Event reports, sequential events recorder (SER), circuit breaker contact wear monitor, substation battery monitor, instantaneous and demand metering, and local display panel.
Reclosing
Programmable four-shot breaker auto-reclose with synchronism and voltage check logic for optimal system restoration.
Communications
Choose from four different channel types for differential communications:
- ITU-T G.703 codirectional to multiplexer
- EIA-422 56/64 kbps
- IEEE C37.94 fiber optic
- 1300nm single mode fiber optic

EIA-232 and EIA-485 serial ports for local/remote access and system integration.
MIRRORED BITS™ communications protocol for eight channels of secure relay-to-relay logic communications available on both rear-panel EIA-232 serial ports.

Download event reports using the optional Ethernet port. Quickly move information with IEC 61850 protocol.

ACSELERATOR^® SEL-5030 Software
Helps speed relay application by allowing you to develop relay settings off-line, program SELOGIC^® control equations, and analyze post-fault event reports.

Single-Pole Tripping
Vertical panel-mount hardware package
Horizontal panel-mount hardware package
DNP 3.0 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.

Complete pilot protection for primary and backup three-pole tripping schemes on transmission and subtransmission lines.
Program up to four shots of automatic breaker reclosing with synchronism and voltage checks to optimize system restoration.
Send synchrophasor data to SCADA and wide-area measurement systems using SEL Fast Messages 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-311 Relays and send it to display and archiving systems, such as SEL-5078 SYNCHROWAVE Console Software.
Use the built-in fault locator to efficiently dispatch line inspection and repair personnel.
Program breaker failure logic with SELOGIC control equations.
Schedule as-needed circuit breaker maintenance and send alarms when the breaker monitor detects excess breaker contact wear from the number of operations and magnitude of interrupted current.
Alarm for low-voltage conditions on station battery.
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.
Use the SEL-311L with IEEE C37.94 fiber-optic interface and fiber-optic cable to connect to an SEL-3094 Interface Converter. The SEL-3094 allows you to use a fiber-optic link to multiplexers that have metallic communications interfaces.

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.

Budgetary Retail, Quantity 1: $6,045
Fully Optioned Price: $10,440
(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.)