ABB Relion REG670, Technical Manual

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Function Range or value Accuracy
Independent time
delay to operate,
undervoltage at 2 to 0
x U
set
(0.00 - 6000.00) s ±0.2% or ±35 ms whichever is
greater
Internal low voltage
blocking
(0.0 - 5.0)% of UBase ±0.25% of U
r
Overcurrent:
Critical impulse time
Impulse margin time
10 ms typically at 0 to 2 x I
set
15 ms typically
-
Undervoltage:
Critical impulse time
Impulse margin time
10ms typically at 2 to 0 x U
set
15 ms typically
-
8.15 Generator stator overload protection, GSPTTR
8.15.1 Identification
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Generator stator overload protection GSPTTR 49S
8.15.2 Functionality
The generator overload function, GSPTTR is used to protect the stator winding
against excessive temperature as a result of overcurrents. The functions operating
characteristic is designed in accordance with the American standard IEEE-C50.13.
If internal generator components exceed its design temperature limit, damage can be
the result. Damage to generator insulation can range from minor loss of life to
complete failure, depending on the severity and duration of the temperature excursion.
Excess temperature can also cause mechanical damage due to thermal expansion.
Since temperature increases with current, it is logical to apply overcurrent elements
with inverse time characteristics.
For its operation the function either measures the true RMS current of the stator
winding or waited sum of the positive and negative sequence components in the stator
winding.
The function is designed to work on 50/60 Hz systems.
1MRK502052-UEN B
Section 8
Current protection
453
Technical manual