Overvoltage Protection 59 - Siemens SIPROTEC 7SJ62 Manual

Functions
2.6 Voltage Protection 27, 59
2.6.2

Overvoltage Protection 59

Function
The overvoltage protection has two elements. In case of a high overvoltage, tripping switchoff is performed with
a short-time delay, whereas in case of less severe overvoltages, the switchoff is performed with a longer time
delay. When one of the adjustable settings is exceeded, the 59 element picks up and trips after an adjustable
time delay has elapsed. The time delay is not dependent on the magnitude of the overvoltage.
The dropout ratio for the two overvoltage elements (= V
The following figure shows the logic diagram of the overcurrent protection function.
Figure 2-45 Logic diagram of the overvoltage protection
142
/V ) can be set.
dropout value pickup value
SIPROTEC, 7SJ62/64, Manual
C53000-G1140-C207-2, Release date 01.2008