1 2 3 4 A - SIPROTEC

Functions
2.1 General
2.1.4 Power System Data 1
2.1.4.1 Topology of the Protected Object
Measured Value Inputs
Type
Terminology
46
The devices of the 7UT6x family comprise various types with different function facilities and different hardware
scope which latter determines the number of available analog inputs. Dependent on the ordering type, the
following analog inputs are provided:
Table 2-1 Analog measuring inputs
For 3-phase protected objects 1) For busbar 1-phase
Current
3-phase 1)
Current (auxiliary) Current Current (auxiliary)
1-phase sensitive 1-phase
2) 1-phase sensitive2) 1) also applicable for single-phase power transformers
2) selectable, contained in the number of 1-phase inputs
Voltage
3-phase
Voltage
1-phase
7UT612 2 2 1 7 2 1 — —
7UT613 3 3 1 9 3 1 1 1
7UT633 3 3 1 9 3 1 1 1
7UT635
5 1 1 — — — — —
4 4 2 12 4 2 — —
The topology of the protected object comprises the totality of all information: how the protected object
(or several objects) is arranged, which current transformer sets supply the currents flowing into the protected
object(s), and which voltages (if available) are measured at which location of the protected object. Thus, the
result of the topological consideration is a complete replica of the protected object(s) with all available measuring
locations. It will be decided at a later stage which measured quantities should be used by which protection
functions (section 2.1.6).
Distinction must be made between the Main Protected Object and other protected objects. The main protected
object is that to which the main protection function, i.e. the differential protection, is applied. This is the power
transformer, generator, motor, etc. as stated under address 105 PROT. OBJECT.
The main protected object has 2 or more sides. The sides of a power transformer are the winding terminals, a
generator or motor is terminated by the terminal side and the starpoint side. In case of combined objects like
generators and transformers in unit connection the sides are the exterior terminals. The expression „side“ is
applied exclusively to the main protected object.
The currents flowing into the protected object are taken from the measuring locations. These are represented
by the current transformers which limit the protected zone. They may be or may not be identical with the sides.
Differences between measurement locations and sides arise, for example, if a power transformer winding
(= 1 side) is fed from 2 galvanically connected lead wires via 2 sets of current transformers (measuring
locations).
The measuring locations which feed a side of the main protected object are the assigned measuring locations.
If the device provides more 3-phase current measuring inputs than are needed for the allocation to the sides
of the main protected object, the remaining measuring points are called non-assigned measuring points. These
can be used for other protection, supervision, and measuring purposes which process 3-phase currents, e.g.
restricted earth fault protection, time overcurrent protection, unbalanced load protection, overload protection,
or simply for display of measured values. The non-assigned measuring points thus detect currents of a further
protected object.
SIPROTEC, 7UT6x, Manual
C53000-G1176-C230-2, Release date 06.2012