Siemens 6MD85, Manual

Page: 1134 / 1256

Y values of the dropout characteristic
curve 0.00 s to 999.00 s Increments of 0.01 s
Dropout Ratio for Stage Type with User-Defined Characteristic Curve (Inverse Time)
Disk emulation Approx. 0.90 * threshold value
Time multiplier Approx. 1.05 * threshold value
Approx. 0.95 * pickup value
Tripping and Dropout Characteristic Curves
You can select from the following tripping and dropout characteristic curves:
Table 11-3 Standard characteristic curves to IEC
Normal inverse: type A See chapter 11.8.2 Stage with Inverse-Time Charac-
teristic Curve , Figure 11-1
Very inverse: type B
Extremely inverse: type C
See chapter 11.8.2 Stage with Inverse-Time Charac-
teristic Curve , Figure 11-2
Long time inverse:
Table 11-4 Standard characteristic curves to ANSI/IEEE
Inverse: type C See chapter 11.8.2 Stage with Inverse-Time Charac-
teristic Curve , Figure 11-3
Short inverse
Long inverse
See chapter 11.8.2 Stage with Inverse-Time Charac-
teristic Curve , Figure 11-4
Moderately inverse
Very inverse
See chapter 11.8.2 Stage with Inverse-Time Charac-
teristic Curve , Figure 11-5
Extremely inverse
Definite inverse
See chapter 11.8.2 Stage with Inverse-Time Charac-
teristic Curve , Figure 11-6
Direction Determination
Type With externally generated voltages
With voltage memory 2 s
Forward range
V
ref,rot
±88 o
Dropout differential forward/reverse range
1 o
Directional sensitivity Unlimited for 1 and 2-phase short circuits
Dynamically unlimited, stationary for 3-phase short
circuits
Approx. 13 V phase-to-phase
Dropout
The greater dropout difference (=
| pickup value – dropout value |
) of the following 2 criteria
applies:
Dropout difference derived from the parameter
Dropout ratio
If this parameter is not available, a dropout ratio of 95 % applies for overcurrent and of 105 % for undercur-
rent functionality.
Minimum absolute dropout difference
Protection-class current transformer
15 mA sec. (I
rated
= 1 A) or
75 mA sec. (I
rated
= 5 A)
Technical Data
11.10 Directional Time-Overcurrent Protection, Phases
1134 SIPROTEC 5, High-Voltage Bay Controller, Manual
C53000-G5040-C015-9, Edition 11.2017