SEL-787 Family Comparison

Windings Protected

2

2

2

3

3

4

CT/PT Inputs

Phase Voltage Inputs

0

0

3

3

3

0

Differential Current Inputs

6

6

6

9

9

12

Neutral Current

0

1

1

1

0

0

VS/VBAT Channel

0

0

0

0

1

0

Differential and Restricted Earth Fault (REF) Elements

Differential Protection Windings (Standard)

2

2

2

3

3

4

REF Elements (Standard)

0

1

1

1

0

0

Differential Protection Windings (Winding 3 Configured for REF)

2

2

3

REF Elements (Winding 3 Configured for REF)

2

2

2

Protection Elements

24

Volts/Hertz

25

Synchronism Check

27I

Inverse-Time Undervoltage (Phase, Phase-to-Phase, Sequential, Vsync)

27P

Undervoltage (Phase) With Inverse Characteristic

27PP

Phase-to-Phase Undervoltage

27S

VS Channel Undervoltage

32

Directional Power

49RTD

Resistance Temperature Detectors (RTDs)

50N

Neutral Overcurrent

50 (P,G,Q)

Overcurrent (Phase, Ground, Neg. Seq.)

51 (P,G,Q)

Time Overcurrent (Phase, Ground, Neg. Seq.)

51N

Neutral Time Overcurrent

51PC

Combined Winding Phase Time Overcurrent

51GC

Combined Winding Ground Time Overcurrent

59 (P,G,Q)

Overvoltage (Phase, Ground, Neg. Seq.)

59

Overvoltage (Synchronism or Battery Voltage)

59I

Inverse-Time Overvoltage (Phase, Phase-to-Phase, Sequential, Vsync)

59S

VS Channel Overvoltage

59Q

Negative-Sequence Overvoltage

81 (O,U)

Over-/Underfrequency

87

Phase Differential

Additional Functions

85RIO

SEL Mirrored Bits Communications

BF

Breaker Failure

BW

Breaker Wear Monitoring

DFR

Event Reports

ENV

SEL-2600 RTD Module Support*

LDP

Load Data Profiling

LGC

SELogic Control Equations

LOP

Loss of Potential

MET

High-Accuracy Metering

RTD

10 Internal or 12 External (See ENV) RTD Inputs*

REF

Restricted Earth Fault

RTU

Remote Terminal Unit

SER

Sequential Events Recorder

TFE

Through-Fault Event Monitor

PMU

Synchronized Phasor Measurement