4.5.9.9 Technical data
Table 653: LVRTPTUV Technical data
Characteristic Value
Operation accuracy Depending on the frequency of the measured voltage:
f 
n
 ±2 Hz
±1.5% of the set value or ±0.002 × U 
n
Start time ,  Typically 40 ms
Reset time Based on maximum value of 
Recovery time
 setting
Operate time accuracy ±1.0% of the set value or ±20 ms
Suppression of harmonics DFT: -50 dB at f = n × f 
n
, where n = 2, 3, 4, 5,…
4.5.10 Voltage vector shift protection VVSPPAM
4.5.10.1 Identification
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE
C37.2 device
number
Voltage vector shift protection VVSPPAM VS 78V
4.5.10.2 Function block
Figure 363: Function block
4.5.10.3 Functionality
The voltage vector shift protection function VVSPPAM, also known as vector surge
or delta phi function, measures continuously the duration of a voltage cycle. At the
instance of islanding, the duration of measured voltage cycle becomes shorter or
longer than the previous one, that is, the measured voltage cycle shifts with time.
This shifting of voltage is measured in terms of phase angle. VVSPPAM issues an
instantaneous trip when the shift in voltage vector exceeds the set value.
The function can be blocked with BLOCK input. Blocking resets timers and outputs.
1
Tested for 
Number of Start phases
 = 1 out of 3, results based on statistical distribution of 1000
measurements
2
Includes the delay of the signal output contact
1MRS757644 H Protection functions
620 series
Technical Manual
695