Functions
2.4 Load Restoration
SIPROTEC, 7RW80, Manual
C53000-G1140-C233-1, Release date 10.2010
61
2.4.2
Setting Notes
General
The load restoration is active, if
Load Restore
=
Enabled
has been set at address
155
during configuration.
If the function is not required
Disabled
is set.
The various elements of the load restoration are configured
ON
orr
OFF
at addresses
5520
,
5540
,
5560
and
5580
.
Pickup- and Dropout Values
At addresses
5521
,
5541
,
5561
and
5581
you may configure the start frequency
LRx Start
for the elements.
The start frequency must be adjusted to a value equal or higher than the tripping frequency of the underfre-
quency element.
At addresses
5523
,
5543
,
5563
and
5583
may configure the pickup frequency
LRx Pickup
for the elements.
The pickup frequency and the start frequency add up to the pickup threshold of the load restoration element.
At addresses
5524
,
5544
,
5564
and
5584
you may configure the delay time
LRx t pickup
for the pickup of
elements.
At addresses
5525
,
5545
,
5565
and
5585
you may configure the dropout frequency
LRx Dropout
the ele-
ments. The dropout frequency and the start frequency add up to the dropout threshold of the load restoration
element.
At addresses
5526
,
5546
,
5566
and
5586
you may configure the dropout time
LRx t dropout
for the ele-
ments.
At addresses
5527
,
5547
,
5567
and
5587
you may configure the close command duration of the circuit
breaker
LRx t CB Close
.
The following example illustrates the interaction of the pickup- and dropout values of the load restoration ele-
ments and underfrequency elements.
The pickup threshold of the underfrequency elements 81 U-1, 81 U-2 and 81 U-3 are set to the following fre-
quencies:
81-1 PICKUP
5403
= 49,5 Hz
81-2 PICKUP
5406
= 49 Hz
81-3 PICKUP
5409
= 47.5 Hz
Table 2-3
Settings Example
Parameter
LR1
LR2
LR3
Start
LR1 Start 5521 = 49,5 Hz
LR2 Start 5541 = 49 Hz
LR3 Start 5561 = 49 Hz
PICKUP
LR1 Pickup 5523 = 0.25 Hz
LR2 Pickup 5543 = 0.5 Hz
LR3 Pickup 5563 = 0.5 Hz
Dropout
LR1 Dropout 5525 = 0 Hz
LR2 Dropout 5545 = 0.25 Hz
LR3 Dropout 5565 = 0.25 Hz
Trip Time
LR1 t pickup 5524 = 14 s
LR2 t pickup 5544 = 13 s
LR3 t pickup 5564 = 7 s
Dropout Time
LR1 t dropout 5526 = 10 s
LR2 t dropout 5546 = 10 s
LR3 t dropout 5566 = 10 s
CB Close time
LR1 t CB Close 5527 = 1 s
LR2 t CB Close 5547 = 1 s
LR3 t CB Close 5567 = 1s
Underfrequency ele-
ments
LR1 after 81-1 5528 = YES
LR1 after 81-2 5529 = YES
LR1 after 81-3 5530 = YES
LR1 after 81-4 5531 = YES
LR2 after 81-1 5548 = NO
LR2 after 81-2 5549 = YES
LR2 after 81-3 5550 = YES
LR2 after 81-4 5551 = YES
LR3 after 81-1 5568 = NO
LR3 after 81-2 5569 = YES
LR3 after 81-3 5570 = YES
LR3 after 81-4 5571 = YES