Seg HighTECH MRU3-2, Руководство пользователя

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TB MRU3-2 12.00 E 5
3.1.1 Analog input circuits
The analog input voltages are galvanically decoupled
by the input transformers of the device, then filtered
and finally fed to the analog digital converter. De-
pending upon the demands the
MRU3-2 can be con-
nected directly to the mains or via external voltage
transformers in star- or delta connection. The priority
should be given to the star connection, because of the
ability to detect a sero sequence system.
3.1.2 Blocking input
When the voltage, which must be in the admissible
range of the auxiliary voltage, is connected to termi-
nals D8/E8, the following tripping functions are
blocked undelayed:
•
undervoltage U</U<<
•
overvoltage U>/U>>
•
positive sequence system undervoltage U1<
•
positive sequence system overvoltage U1>
•
negative sequence system overvoltage U2>
•
zero sequence system overvoltage U0>
Blocking can be freely selected via the allocation
mode. (refer to chapter 5.9).
Input D8 is the ground (L- or N) for blocking and the
external reset. The blocked functions are again re-
leased undelayed when the auxiliary voltage is dis-
connected from the terminals D8/E8.
The above mentioned functions remain blocked for 2 s
after the supply voltage had been applied.
3.1.3 External reset input
Refer to chapter 5.9.2
3.1.4 Output relays
The MRU3-2 is equipped with 5 output relays.
•
Relay 1; C1, D1, E1 and C2, D2, E2
•
Relay 2; C3, D3, E3 and C4, D4, E4
•
Relay 3; C5, D5, E5
•
Relay 4; C6, D6, E6
•
Relay 5; Signal self-supervision (internal failure of
the unit ) C7, D7, E7
All trip and alarm relays are working current relays, the
relay for self supervision is an idle current relay.
3.1.5 Fault recorder
The MRU3-2 has a fault value recorder which records
the measured analog values as instantaneous values.
The instantaneous values
U
L1
; U
L2
; U
L3
for star connection
or U
12
; U
23
; U
31
for delta connection
are scanned at a raster of 1.25 ms (at 50 Hz) and
1.041 ms (at 60 Hz) and saved in a cyclic buffer.
Storage division
Independent of the recording time, the entire storage
capacity can be divided into several cases of distur-
bance with a shorter recording time each. In addition,
the deletion behaviour of the fault recorder can be in-
fluenced.
No writing over
If 2, 4 or 8 recordings are chosen, the complete
memory is divided into the relevant number of partial
segments. If this max. number of fault event has been
exceeded, the fault recorder block any further record-
ings in order to prevent that the stored data are written
over. After the data have been read and deleted, the
recorder to ready again for further action.