FUNCTION CHARACTERISTICS
185
NVA100X-D - Manual - 02 - 2016
Negative sequence overvoltage - 59V2
Preface
The element has an adjustable threshold with time defi nite delay.
Enabling or disabling may be performed through ThySette.
Operation and settings
The negative sequence voltage is calculated as:
U
2
=(
U
L1
+e
-j120°
·
U
L2
+e
+j120°
·
U
L3
)/3
where e
-j120°
=-1/2-j√3/2, e
j120°
=-1/2+j√3/2.
The negative sequence voltage is compared with the setting value (
U
2
>
def
).
Voltages above the associated pickup value are detected and a start is issued. After expiry of the
associated operate time (
t
U12
>
def
) a trip command is issued; if instead the voltage drops below the
threshold, the element is restored.
The element can be enabled or disabled by setting
ON
or
OFF
the
State
parameter inside the
Set \
Profi le A(or B) \ Negative sequence overvoltage-27V2 \
U2> Element \ Setpoints
menu.
Breaker failure (BF)
The 59V2 element can produce the Breaker Failure output if the
U2>BF
parameter is set to
ON.
The parameters are available inside the
Set \ Profi le A(or B) \Negative sequence overvoltage-59V2
\ U2> Element \ Setpoints
menu.
[1]
Logical block (Block1)
If the
U2>BLK1
enabling parameter is set to
ON
and a binary input is designed for logical block
(Block1), the protection is blocked off whenever the given input is active.
The trip timer is held in reset condition, so the operate time counting starts when the input block goes
down.
[2]
The enabling parameters are available inside the
Set \ Profi le A(or B) \Negative sequence
overvoltage-59V2 \ U2> Element \ Setpoints
menu, while the
Block1
function must be assigned to
the selected binary input inside the
Set \ Board1(2) inputs \ Binary input IN1-1...INx-x)
menus.
All the parameters can be set separately for
Profi le A
and
Profi le B
.
Note 1 The common settings concerning the Breaker failure protection are adjustable inside the
Breaker Failure - BF
menu.
Note 2 The exhaustive treatment of the logical block (Block 1) function may be found in the “Logic Block” paragraph inside
CONTROL AND MONITOR-
ING
section.
—
t-int-F59V2.ai
U
2
U
2
>
def
t
t
U 2
>
def
General operation time characteristic for the positive overvoltage element - 59V2
TRIP
all-597V2.ai
General operation time characteristic for the positive overvoltage element - 59V2
U2> Element
Start U2>
Trip U2>
t
U2> def
U
2
>
def
State
Block1
BLK1U2>
&
U2>BLK1
Start U2>
&
U2>BF
Trip U2>
&
U2>BF
U
2
