2.19 Rate-of-Frequency-Change Protection df/dt (ANSI 81R)
121
7UM61 Manual
C53000-G1176-C127-3
Setting changes are necessary e.g. to obtain a great dropout difference. For the de-
tection of very small frequency changes (< 0.5 Hz/s), the default setting of the mea-
suring window should be extended. This is to improve the measuring accuracy.
Minimum Voltage
Address
4518
U MIN
is used to set the minimum voltage below which the frequency
change protection will be blocked. A value of approx. 65 % U
N
is recommended. The
minimum voltage threshold can be deactivated by setting this address to “0”.
2.19.3 Settings
Addresses which have an appended "A" can only be changed with DIGSI, under Ad-
ditional Settings.
Setting value
Stage df
n
/dt
df/dt HYSTERES.
(Addr. 4519, 4521)
dfx/dt M-WINDOW
(Addr. 4520, 4522)
0.1...0.5 Hz/s
≈
0.05
25...10
0.5...1 Hz/s
≈
0.1
10...5
1...0.5 Hz/s
≈
0.2
10...5
5...00.10 Hz/s
≈
0.5
5...1
Addr.
Parameter
Setting Options
Default Setting
Comments
4501
df/dt Protect.
OFF
ON
Block relay
OFF
Rate-of-frequency-change pro-
tection
4502
df1/dt >/<
-df/dt<
+df/dt>
-df/dt<
Mode of Threshold (df1/dt >/<)
4503
STAGE df1/dt
0.1 .. 10.0 Hz/s;
∞
1.0 Hz/s
Pickup Value of df1/dt Stage
4504
T df1/dt
0.00 .. 60.00 sec;
∞
0.50 sec
Time Delay of df1/dt Stage
4505
df1/dt & f1
OFF
ON
OFF
AND logic with pickup of stage f1
4506
df2/dt >/<
-df/dt<
+df/dt>
-df/dt<
Mode of Threshold (df2/dt >/<)
4507
STAGE df2/dt
0.1 .. 10.0 Hz/s;
∞
1.0 Hz/s
Pickup Value of df2/dt Stage
4508
T df2/dt
0.00 .. 60.00 sec;
∞
0.50 sec
Time Delay of df2/dt Stage
4509
df2/dt & f2
OFF
ON
OFF
AND logic with pickup of stage f2
4510
df3/dt >/<
-df/dt<
+df/dt>
-df/dt<
Mode of Threshold (df3/dt >/<)
4511
STAGE df3/dt
0.1 .. 10.0 Hz/s;
∞
4.0 Hz/s
Pickup Value of df3/dt Stage
4512
T df3/dt
0.00 .. 60.00 sec;
∞
0.00 sec
Time Delay of df3/dt Stage
4513
df3/dt & f3
OFF
ON
OFF
AND logic with pickup of stage f3
4514
df4/dt >/<
-df/dt<
+df/dt>
-df/dt<
Mode of Threshold (df4/dt >/<)
4515
STAGE df4/dt
0.1 .. 10.0 Hz/s;
∞
4.0 Hz/s
Pickup Value of df4/dt Stage
4516
T df4/dt
0.00 .. 60.00 sec;
∞
0.00 sec
Time Delay of df4/dt Stage
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Содержание Siprotec 7UM611
Страница 16: ...Contents 16 7UM61 Manual C53000 G1176 C127 3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 232: ...2 Functions 232 7UM61 Manual C53000 G1176 C127 3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 292: ...3 Mounting and Commissioning 292 7UM61 Manual C53000 G1176 C127 3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 410: ...A Appendix 410 7UM61 Manual C53000 G1176 C127 3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...
Страница 412: ...Literature 412 7UM61 Manual C53000 G1176 C127 3 w w w E l e c t r i c a l P a r t M a n u a l s c o m ...