ABB REG650 ANSI, Техническое руководство

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Function Range or value Accuracy
Operate time, non-directional
residual overvoltage
45 ms typically at 0.8 to 1.5 x
U
set
45 ms typically at 0.8 to 1.5 x U
set
Reset time, non-directional
residual overvoltage
85 ms typically at 1.2 to 0.8 x
U
set
85 ms typically at 1.2 to 0.8 x U
set
Operate time, directional
residual over current
140 ms typically at 0.5 to 2 x
I
set
-
Reset time, directional
residual over current
85 ms typically at 2 to 0.5 x I
set
-
Critical impulse time non-
directional residual over
current
35 ms typically at 0 to 2 x I
set
-
Impulse margin time non-
directional residual over
current
25 ms typically -
8.4 Thermal overload protection, two time constants
TRPTTR
8.4.1 Identification
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Thermal overload protection, two time
constants
TRPTTR
SYMBOL-A V1 EN
49
8.4.2 Functionality
If a power transformer or generator reaches very high temperatures the equipment
might be damaged. The insulation within the transformer/generator will have forced
ageing. As a consequence of this the risk of internal phase-to-phase or phase-to-earth
faults will increase. High temperature will degrade the quality of the transformer/
generator insulation.
The thermal overload protection estimates the internal heat content of the transformer/
generator (temperature) continuously. This estimation is made by using a thermal
model of the transformer/generator with two time constants, which is based on current
measurement.
Two warning levels are available. This enables actions in the power system to be done
before dangerous temperatures are reached. If the temperature continues to increase to
the trip value, the protection initiates a trip of the protected transformer/generator.
Section 8
1MRK 502 048-UEN A
Current protection
214
Technical manual