Feeder_3 logic scheme, Normal operation - control, Normal operation - protection – Basler Electric BE1-851 User Manual

Page 182: Normal operation - reclosing, Feeder_3 logic scheme -26, Normal operation - control -26, Normal operation - protection -26, Normal operation - reclosing -26

Advertising
background image

SL-143 = 2

SL-243 = 2

SL-343 = 2

SL-101 = 1

SL-VOA = ALMMAJ

SL-VO1 = VO11+BFPU+101T

SL-VO2 = 79C+101C

SL-VO3 = IN4*/343

SL-VO4 = VO12*/VO5*IN4*/343

SL-VO5 = BFT

SL-VO6 = 0

SL-VO7 = 0

SL-VO8 = VO11

SL-VO9 = /IN2+143+/101SC+VO5+150TPT+150TNT

SL-VO10 = VO11

SL-VO11 = 50TPT+50TNT+150TPT+150TNT+51PT+51NT

SL-VO12 = 50TPPU+50TNPU+150TPPU+150TNPU+51PPU+51NPU

SL-VO13 = 0

SL-VO14 = 0

SL-VO15 = /IN4+343

Feeder_3 Logic Scheme

Logic scheme Feeder_3 is meant for use on a feeder breaker and provides all overcurrent and breaker

failure protection, reclosing, and control functions required for a typical feeder in a non-directional

overcurrent protection application. This logic scheme is intended for use in conjunction with other

programmable relays using BUS and BACKUP schemes to provide protection when the relay is out of

service.
Automatic reclosing is initiated by the breaker opening. Reclosing is disabled after a manual trip by a

control switch slip contact. In this logic scheme, the disable logic is connected to the drive to lockout

(DTL) input. The recloser will remain in lockout until the breaker closes and the reset timer times out.
When used with other programmable relays using logic scheme BUS and BACKUP, this scheme can

provide complete high-speed overcurrent protection for the transformers, bus, and feeders in a radial

system substation.
The components of Feeder_3 logic are summarized in Tables 8-13 through 8-16. Figure 8-7 is a one-line

diagram of Feeder_3 logic and Figure 8-8 is a diagram representing the logic settings and equations of

Feeder_3 logic.

Normal Operation - Control

The virtual breaker control switch is programmed to provide manual trip and close control of the breaker.

Control functions of this logic scheme use traditional contact sensing inputs and virtual switches. Virtual

switches that are not needed may simply go unused. The protection engineer may choose to free up

contact sensing inputs for other uses by using the virtual switches exclusively for control functions.

Normal Operation - Protection

All overcurrent function blocks and the breaker failure function block re-trip output are enabled in

Feeder_3 logic for tripping via OUT1. The 150T function blocks are set up as high set instantaneous

functions which drive the recloser to lockout when they trip. Setting the pickup at zero in the four setting

groups can individually disable each overcurrent function block. The 50TN, 50TQ, 51N, and 51Q function

blocks are torque controlled by either IN3 or Virtual Switch 243. All N and Q function blocks or only the

51N and 51Q function blocks may be inhibited. This is done in BESTlogic by modifying the inputs to the

function blocks.

Normal Operation - Reclosing

The reclosing logic in Feeder_3 is initiated by the breaker opening. Automatic reclosing is disabled for a

manual trip by a control switch slip contact. Setting the first reclose time can disable the recloser function

block = zero in the four setting groups.
8-26

BE1-851 Application

9289900990 Rev R

Advertising