Siemens SIPROTEC 7UT613 series, Руководство пользователя

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2.14 Undervoltage Protection
257
7UT613/63x Manual
C53000-G1176-C160-2
The respective delay time
T U<
(address
5213
) is supposed to bridge the permissible
short-term voltage dips during continuous undervoltage, which may lead to an unsta-
ble operation, however, it is supposed to be switched off within a few seconds.
For the U<< stage, a lower pickup threshold with a short delay should be set so that
in case of heavy voltage dips a quick trip can occur, e.g. 65 % of the nominal voltage
with 0.5 s delay.
If the undervoltage protection is assigned to one side of the main protected object or
the three-phase busbar, the pickup value must be set as reference value under
address
5215 U<<
, e.g. 0.65. When assigned to a measuring location, the value of
phase-phase voltage must be set under address
5214 U<<
in Volt, e.g. 71.5. V at
U
N sec
= 110 V (65 % of 110 V).
The set times are additional time delays that do not include the operating time (mea-
suring time, dropout time) of the protection function. If a delay time is set to
∞
, this
does not result in a trip, however, the pickup will be indicated.
Dropout Ratio The drop-out ratio can be adjusted to the operating conditions at address
5217 DOUT
RATIO
. This parameter can only be altered in DIGSI at Additional Settings .
2.14.3 Settings
Addresses which have an appended "A" can only be changed with DIGSI, under Ad-
ditional Settings.
2.14.4 Information List
Addr. Parameter Setting Options Default Setting Comments
5201 UNDERVOLTAGE OFF
ON
Block relay OFF Undervoltage Protection
5211 U< 10.0 .. 125.0 V 75.0 V U< Pickup
5212 U< 0.10 .. 1.25 U/UnS 0.75 U/UnS Pick-up voltage U<
5213 T U< 0.00 .. 60.00 sec;
∞
3.00 sec T U< Time Delay
5214 U<< 10.0 .. 125.0 V 65.0 V U<< Pickup
5215 U<< 0.10 .. 1.25 U/UnS 0.65 U/UnS Pick-up voltage U<<
5216 T U<< 0.00 .. 60.00 sec;
∞
0.50 sec T U<< Time Delay
5217A DOUT RATIO 1.01 .. 1.20 1.05 U<, U<< Drop Out Ratio
No. Information Type of In-
formation
Comments
033.2404 >BLOCK U/V SP >BLOCK undervoltage protection
033.2411 Undervolt. OFF OUT Undervoltage protection is switched OFF
033.2412 Undervolt. BLK OUT Undervoltage protection is BLOCKED
033.2413 Undervolt. ACT OUT Undervoltage protection is ACTIVE
033.2491 U< err. Obj. OUT Undervoltage: Not avail. for this obj.
033.2492 U< err. VT OUT Undervoltage: error assigned VT