Tolerances
Voltages 0.5 % of the setting value or 0.05 V
Time delays 1 % of the setting value or 10 ms
Undervoltage Protection with 3-Phase Voltage
Setting Values for Stage Type Definite Time-Undervoltage Protection
Measured value Phase-to-phase
Phase-to-ground
Method of measurement Fundamental component
RMS value
Current-flow criterion On
Off
Threshold value I> 1 A @ 50 and 100 Irated 0.030 A to 10.000 A Increments of 0.001 A
5 A @ 50 and 100 Irated 0.15 A to 50.00 A Increments of 0.01 A
1 A @ 1.6 Irated 0.001 A to 1.600 A Increments of 0.001 A
5 A @ 1.6 Irated 0.005 A to 8.000 A Increments of 0.001 A
Threshold value
64
0.300 V to 175.000 V Increments of 0.001 V
Time delay 0.00 s to 60.00 s Increments of 0.01 s
Dropout ratio 1.01 to 1.20 Increments of 0.01
Setting Values for Stage Type Inverse Time-Undervoltage Protection
Measured value
Phase-to-phase
Phase-to-ground
Method of measurement Fundamental component
RMS value
Current-flow criterion On
Off
Threshold value I> 1 A @ 50 and 100 Irated 0.030 A to 10.000 A Increments of 0.001 A
5 A @ 50 and 100 Irated 0.15 A to 50.00 A Increments of 0.01 A
1 A @ 1.6 Irated 0.001 A to 1.600 A Increments of 0.001 A
5 A @ 1.6 Irated 0.005 A to 8.000 A Increments of 0.001 A
Threshold value 0.300 V to 175.000 V Increments of 0.001 V
Pickup factor 0.80 to 1.00 Increments of 0.01 
Characteristic constant k 0.00 to 300.00 Increments of 0.01 
Characteristic constant α 0.010 to 5.000 Increments of 0.001 
Characteristic constant c 0.000 to 5.000 Increments of 0.001 
Time multiplier 0.05 to 15.00 Increments of 0.01
Additional time delay 0.00 s to 60.00 s Increments of 0.01 s
Reset time 0.00 s to 60.00 s Increments of 0.01 s
Operate Curve
T
op
=T
Inv
+ T
add
Where:
T
op
Operate delay
12.10.6
64
If you have selected the Method of measurement = RMS value, do not set the threshold value to less than 10 V.
Technical Data
12.10 Voltage Protection
SIPROTEC 5, Merging Unit 6MU85, Manual 839
C53000-G5040-C074-1, Edition 01.2020