GE L30 User Manual

GE Multilin L30 Line Current Differential System 5-237
5 SETTINGS 5.7 CONTROL ELEMENTS
5
• CT FAIL 1 3V0 INPUT: This setting selects the voltage source.
• CT FAIL 1 3V0 INPUT PICKUP: This setting specifies the pickup value for the 3V_0 source.
• CT FAIL 1 PICKUP DELAY: This setting specifies the pickup delay of the CT failure element.
Figure 5–106: CT FAILURE DETECTOR SCHEME LOGIC
d) VT FUSE FAILURE
PATH: SETTINGS  CONTROL ELEMENTS  MONITORING ELEMENTS  VT FUSE FAILURE 1(2)
Every signal source includes a fuse failure scheme.
The VT fuse failure detector can be used to raise an alarm and/or block elements that may operate incorrectly for a full or
partial loss of AC potential caused by one or more blown fuses. Some elements that might be blocked (via the BLOCK input)
are distance, voltage restrained overcurrent, and directional current.
There are two classes of fuse failure that occur:
• Class A: loss of one or two phases.
• Class B: loss of all three phases.
Different means of detection are required for each class. An indication of class A failures is a significant level of negative-
sequence voltage, whereas an indication of class B failures is when positive sequence current is present and there is an
insignificant amount of positive sequence voltage. Also rapid decrease in the phase voltages magnitude from a healthy
voltage level without disturbance in current can indicate a VT fuse fail conditions. These noted indications of fuse failure
can also be present when faults are present on the system, so a means of detecting faults and inhibiting fuse failure decla-
rations during these events is provided.
 VT FUSE FAILURE 1

VT FUSE FAILURE 1
FUNCTION: Disabled
Range: Disabled, Enabled
MESSAGE
 NEUTRAL WIRE OPEN 1
 DETECTION: Disabled
Range: Disabled, Enabled
MESSAGE
 NEUTRAL WIRE OPEN 1
 3 HARM PKP: 0.100
Range: 0.000 to 3.000 pu in steps of 0.001
CT FAIL 1 FUNCTION:
CT FAIL 1 BLOCK:
CT FAIL 1 3IO INPUT1: CT FAIL 1 3IO INPUT1 PKP:
CT FAIL 1 3VO INPUT: CT FAIL 1 3VO INPUT:
CT FAIL 1 3IO INPUT2: CT FAIL 1 3IO INPUT2 PKP:
CT FAIL 1 PICKUP DELAY:
AND
OR
SETTING
Enabled=1
SETTING
SETTING SETTING
SETTING SETTING
SETTING SETTING
SETTING
Off=0
SRC1 RUN 3IO > PICKUP
3IO > PICKUP
3VO > PICKUPSRC1 RUN
SRC2 RUN
FLEXLOGIC OPERANDS
CT FAIL 1 OP
CT FAIL 1 PKP
827048A8.CDR
0

GE L30 Specifications

General

Brand	GE
Model	L30
Category	Relays
Language	English