SEL-551 Overcurrent/Reclosing Relay

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

SEL-551

Overcurrent/Reclosing Relay

Combine overcurrent protection and multiple-shot reclosing in one compact relay.

Comprehensive Overcurrent Protection
Phase, negative-sequence, residual ground, and neutral overcurrent protection in a compact package. Complete set of instantaneous, definite-time, and time-overcurrent elements.
Reclosing
Program up to four shots of reclosing with sequence coordination logic for coordination with downstream reclosers.
ACSELERATOR^® QuickSet 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.
Protection and Control Logic
SELOGIC control equations with SELOGIC variables and timers allow traditional or advanced protection schemes. Programmable local control elements permit front-panel pushbutton control. Programmable text display points provide enhanced local operator information.
Monitoring and Reporting
Instantaneous, peak, and demand metering. The latest twenty 15-cycle oscillographic data event reports and the latest 256 Sequential Events Recorder (SER) records are stored in nonvolatile memory.
Communications
ASCII, binary, and Modbus^® RTU protocols enhance integration capabilities.

SEL accessories simplify operation and enhance the flexibility of SEL products.

Add independent breaker control to any relay. The SEL-9510 Control Switch Module easily installs in panel or rack locations for independent local control and status indications.

SEL-9510 and 500 series

SEL provides options to help you efficiently and safely commission and test these relays.
	Streamline commissioning by using the SEL-4391 Data Courier™ 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-551 relays.

Panel-mount or rack-mount hardware package.
Connectorized packaging includes high-current interrupting output contacts.
EIA-232 or EIA-485 serial communications — either port includes a demodulated IRIG-B time-code input.
Bracket with mounting hole for FT-1 switch (switch not included) to mount one 500 series relay in a 19-inch rack.
Conformal Coating—Protect equipment from harsh environments and airborne contaminants such as hydrogen sulfide, chlorine, salt, and moisture.
Learn more about conformal coating.

Protect distribution feeders, distribution buses, transformers, capacitors, and circuit breakers.
Select the "fast bus" trip scheme when protecting a distribution bus.
Choose "fast" or "slow" curve operation to allow for cold load pickup.
Connect the separate neutral current input to accommodate core-balance current transformers, separate neutral current transformers, tertiary winding current transformers, or CT ground residual circuits.
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.

Budgetary Retail, Quantity 1: $840
Fully Optioned Price: $1,182
(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.)