ABB REB670 Series, Руководство по применению

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4.2.1.1 Example
SEMOD55055-11 v5
Usually the L1 phase-to-earth voltage connected to the first VT channel number of the
transformer input module (TRM) is selected as the phase reference. The first VT channel
number depends on the type of transformer input module.
For a TRM with 6 current and 6 voltage inputs the first VT channel is 7. The setting
PhaseAngleRef=7 shall be used if the phase reference voltage is connected to that channel.
4.2.2 Setting of current channels
SEMOD55055-16 v6
The direction of a current to the IED is depending on the connection of the CT. Unless
indicated otherwise, the main CTs are supposed to be star connected and can be connected
with the earthing point to the object or from the object. This information must be set in the
IED. The convention of the directionality is defined as follows: A positive value of current,
power, and so on means that the quantity has the direction into the object and a negative
value means direction out from the object. For directional functions the direction into the
object is defined as Forward and the direction out from the object is defined as Reverse. See
Figure 13
A positive value of current, power, and so on (forward) means that the quantity flows towards
the object. A negative value of current, power, and so on (reverse) means that the quantity
flows away from the object. See Figure 13 .
Protected Object
Line, transformer, etc
Forward Reverse
Definition of direction
for directional functions
Measured quantity is
positive when flowing
towards the object
e.g. P, Q, I
Reverse Forward
Definition of direction
for directional functions
e.g. P, Q, I
Measured quantity is
positive when flowing
towards the object
Set parameter
CTStarPoint
Correct Setting is
"ToObject"
Set parameter
CTStarPoint
Correct Setting is
"FromObject"
en05000456.vsd
IEC05000456 V1 EN-US
Figure 13: Internal convention of the directionality in the IED
With correct setting of the primary CT direction,
CTStarPoint set to FromObject or ToObject, a
positive quantities always flowing towards the protected object and a direction defined as
Forward always is looking towards the protected object. The following examples show the
principle.
4.2.2.1 Example 1
SEMOD55055-23 v6
Two IEDs used for protection of two objects.
Section 4 1MRK 505 370-UEN D
Analog inputs
60 Busbar protection REB670
Application manual