SEL-587Z High-Impedance Differential Relay

The SEL-587Z Relay is a flexible high-impedance differential relay that combines time-proven high-impedance analog technology with the advantages of microprocessor technology. Use event reports and Sequential Event Recorder (SER) for quick post-event analysis.

Functional Overview

50	(P,G,Q) Overcurrent (Phase, Ground, Neg. Seq.)
51	(P,G,Q) Time-Overcurrent (Phase, Ground, Neg. Seq.)
87	Three-Phase Current Differential
DFR	Event Reports
HMI	Operator Interface
LGC	Expanded SELogic Control Equations
MET	High-Accuracy Metering
SER	Sequential Events Recorder

* Optional

Front- and Rear-Panel Diagrams


Front		Rear

Protection

Use high-impedance differential elements for fast tripping for in-zone faults, while providing security during heavy through faults and CT saturation. Reduce panel design cost and space requirements by using a single relay that includes three-phase protection, resistors, and metal oxide varistors (MOVs).

Control

Use front-panel pushbuttons to save the expense of separately mounted control switches. Serial port communication provides for remote control of circuit breakers or other user-defined functions.

Reporting, Monitoring, and Metering

Simplify fault analysis with event reports and Sequential Events Recorder (SER). Validate CT connections using the metered voltagedifferential quantities.

Communications

Integrate the relay with SCADA, local HMI, or modems using Modbus®, SEL ASCII, and SEL Fast Messaging protocols through the rear-panel isolated communications port. Use the front-panel communications port for relay settings and event report retrieval

Comparison

487B

587Z

APPLICATIONS

Breaker Failure Protection	•	f
Bus Differential	•	•
High-Impedance Bus Differential		•
Low-Impedance Bus Differential	•
Three-Phase Current Inputs	7/10 /21	Com- mon
Three-Phase Voltage Inputs	1

PROTECTION

27/59 Under-/Overvoltage	•
46 Current Unbalance	f
50 (N,G) Overcurrent (Neutral, Ground)		•
50P Phase Overcurrent	•	•
50Q Negative-Sequence Overcurrent		•
51 (N,G) Time-Overcurrent (Neutral, Ground)		•
51P Phase Time-Overcurrent	•	•
51Q Negative-Sequence Time-Overcurrent		•
87 Current Differential	•
87Z High-Impedance Differential		•
Single-Pole Trip/Close	•
Three-Phase Differential Bus Zones	2/3/6	1
Check Zones	3

INSTRUMENTATION AND CONTROL

79 Automatic Reclosing	f
Dynamic Zone Selection	•
SELogic Control Equations	•	•
Nonvolatile Latch Control Switches	•
SELogic Remote/Local Control Switches	•	•
Display Points	•	•
Multiple Settings Groups	•
Substation Battery Monitor	•
Event Report (Multicycle Data)	•	•
Sequential Events Recorder	•	•
Instantaneous Meter	•	•
Demand Meter		•
IEC 61850	+
Built-In Web Server	•
Simple Network Time Protocol (SNTP)	•
Mirrored Bits Communications	•
Parallel Redundancy Protocol (PRP)	•

MISCELLANEOUS FEATURES

Connectorized (Quick Disconnect) Available

•	Standard Feature
+	Model Option
f	This function may be created using settings