Siemens 6MD85, Manual

Page: 1156 / 1256

[fo_UVP3ph_inverse, 2, en_US]
Where
T
Inv
Inverse-time delay
T
p
Time multiplier (parameter
Time dial
)
V Measured undervoltage
V
Thresh
Threshold value (parameter
Threshold
)
k Curve constant k (parameter
Charact. constant k
)
α Curve constant α (parameter
Charact. constant α
)
c Curve constant c (parameter
Charact. constant c
)
Dropout
The greater dropout differential (=
| pickup value – dropout value |
) of the following 2 criteria
applies:
Dropout differential derived from the parameter
Dropout ratio
If this parameter is not available, a dropout ratio of 95 % applies for the overvoltage and of 105 % for the
undervoltage functionality.
Minimum absolute dropout differential
150 mV sec.
Times
Pickup time
Approx. 25 ms + OOT 76 at 50 Hz
Approx. 22 ms + OOT at 60 Hz
Dropout time Approx. 20 ms + OOT
Frequency Operating Range
0.9 ≤ f/f
rated
≤ 1.1 According to specified tolerances
10 Hz ≤ f < 0.9 f
rated
1.1 f
rated
< f ≤ 80 Hz
Slightly expanded tolerances
f < 10 Hz
f > 80 Hz Inactive, maintained;
Dropout of the pickup induced by blocking or by
increasing the measurand beyond the dropout
threshold
Tolerances for Stage Type Definite-Time Undervoltage Protection
Voltages 0.5 % of the setting value or 0.05 V
Currents 1 % of the setting value or 5 mA (I
rated
= 1 A) or 25 mA
(I
rated
= 5 A, f
rated
± 10 %), valid for protection-class
current transformers
1 % of the setting value or 0.1 mA (I
rated
= 1.6 A) or
0.5 mA (I
rated
= 8 A, f
rated
± 10 %), valid for instrument
transformers
Time delays 1 % of the setting value or 10 ms
76 OOT (Output Operating Time): additional delay of the output medium used, see Chapter 11.1.4 Relay Outputs
Technical Data
11.20 Undervoltage Protection with 3-Phase Voltage
1156 SIPROTEC 5, High-Voltage Bay Controller, Manual
C53000-G5040-C015-9, Edition 11.2017