ABB Relion 670 Series RES670, Technical Manual

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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"
en05000456-2.vsd
ANSI05000456 V2 EN
Figure 2: Internal convention of the directionality in the IED
If the settings of the primary CT is correct, that is CTStarPoint set as FromObject or
ToObject according to the plant condition, then a positive quantity always flows towards
the protected object, and a Forward direction always looks towards the protected object.
The settings of the IED is performed in primary values. The ratios of the main CTs and
VTs are therefore basic data for the IED. The user has to set the rated secondary and
primary currents and voltages of the CTs and VTs to provide the IED with their rated
ratios.
The CT and VT ratio and the name on respective channel is done under Main menu/
Hardware/Analog modules in the Parameter Settings tool or on the HMI.
3.7 Technical data
Table 27: TRM - Energizing quantities, rated values and limits for protection transformer modules
Quantity Rated value Nominal range
Current I
n
= 1 or 5 A (0.2-40) × I
n
Operative range (0-100) x I
n
Permissive overload 4 × I
n
cont.
100 × I
n
for 1 s
*)
Burden < 150 mVA at I
n
= 5 A
< 20 mVA at I
n
= 1 A
Ac voltage V
n
= 120 V 0.5–288 V
Operative range (0–340) V
Table continues on next page
Section 3
1MRK 511 365-UUS A
Analog inputs
68 Phasor measurement unit RES670 2.1 ANSI
Technical manual