FUNCTION CHARACTERISTICS
117
NVA100X-D - Manual - 02 - 2016
Phase rotation direction check - 47
Preface
The starting of synchronous motors is inhibited when the 47 function becomes active.
The element can be enabled or disabled.
Operation and settings
The positive sequence voltage is computed as:
U
1
=(
U
L1
+e
+j120°
·
U
L2
+e
-j120°
·
U
L3
)/3
with e
-j120°
=-1/2-j√3/2, e
j120°
=-1/2+j√3/2.
The positive sequence voltage is compared with the setting threshold (
U
s1
<); voltages lower than
the associated pickup value are detected and a start is issued if all the phase-to-phase voltages are
larger than an adjustable threshold (
U
s
>).
The element can be enabled or disabled by setting
ON
or
OFF
the
47Enable
parameter inside the
Set \ Profi le A(or B) \ Phase rotation direction check 47 \
47 Element \ Setpoints
menu.
Logical block (Block1)
If the
47BLK1
enabling parameter is set to
ON
and a binary input is designed for logical block
(Block1), the element is blocked off whenever the given input is active.
[1]
The enabling parameter is available inside the
Set \ Profi le A(or B) \ Phase rotation direction check
47 \
47 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
menu.
Note 1 The exhaustive treatment of the logical block (Block 1) function may be found in the “Logic Block” paragraph inside
CONTROL AND MONITOR-
ING
section
—
Fun-F47_S1.ai
Phase rotation direction check - 47
TRIP
P
ING
M
ATRIX
(LED
+R
EL
AY
S
)
47TR-K
47TR-L
Trip 47
BLK147
&
Enable (ON
≡
Enable)
47BLK1
Block1
Block1
U
1
Binary input INx
T
0
Logic
INx
t
ON
INx
t
ON
INx
t
OFF
T
0
n.o.
n.c.
INx
t
OFF
U
1
≤
U
S1
<
&
&
U
12
U
23
U
31
U
12
≥
U
S
>
U
S
>
ON
≡
Enable 47 element
47 Enable
U
S1
<
