ERL L-PRO 4000, Руководство пользователя

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4 Protection Functions and Specifications
4-2 L-PRO 4000 User Manual D02706R02.30
Event Recording ...... page 4-52
Record Initiation ...... page 4-52
Record Duration and Extension ...... page 4-53
Record Storage ...... page 4-53
Record Retrieval and Deletion ...... page 4-53
Event Log ...... page 4-54
Fault Log ...... page 4-55
4.1 Protection and Recording Functions
Introduction
This section describes the equations and algorithms of the relay protection
functions. All functions with time delay provide an alarm output when their
pickup level is exceeded.
The following functions are exceptions: 27 Auxiliary, 27 Main, 59 Auxiliary,
59 Main, 25/27/59 Sync Check, 50LS Main, 50LS Auxiliary, 50BF Main,
50BF Auxiliary, 81 Frequency and ProLogic elements.
A complete list of the settings and their range values can be found in “IED Set-
tings and Ranges” in Appendix B.
21P Phase/21N
Ground
Distance
The relay 21P contains 5 zones of phase distance elements; all 5 zones of 21P
can be set to either Mho or Quadrilateral type. Note that only one type can be
used at a time. The 21P can contain a mixture of Mho and Quadrilateral shapes,
for example the 21P1 and 21P2 can be set to a Mho characteristic and the 21P3,
21P4 and 21P5 could be set to a Quadrilateral characteristic.
The relay 21N contains 5 zones of ground distance elements; all 5 zones of 21N
can be set to either Mho or Quadrilateral type. Note that only one type can be
used at a time. The 21N can contain a mixture of Mho and Quadrilateral
shapes, for example the 21N1 and 21N2 can be set to a Mho characteristic and
the 21N3, 21N4 and 21N5 could be set to a Quadrilateral characteristic.
The Quadrilateral shape is parallel to the positive sequence line angle setting.
The user-defined Mho Characteristic Angle is not selectable when a Quadrilat-
eral characteristic for that particular zone is defined. All other settings are se-
lectable and user-definable.
Zones 3, 4 and 5 reach can be set in either forward direction or reverse direction
or offset as required. All the distance functions are set in secondary ohms. The
available range of impedance settings is based on the nominal current specified
when the relay was ordered. The impedance reach ranges are given in “21P
Phase/21N Ground Distance” on page 4-2.