Overvoltage Protection 59 Of Side 2 - Siemens 7SC80 Manual

Functions
2.30 Additional Applications with 6 Voltage Inputs
Function Three-phase connec-
tione Side 2 (Param-
Undervoltage protec-
V2an,V2bn,V2cn
tion 27 of side 2
V2a2b,V2b2c,VGn
V2a2b, V2b2c
The positive-sequence voltage in the table is calculated from the phase-to-ground voltage.
Current Criterion
Depending on the system, the primary voltage transformers are arranged either on the supply side or the load
side of the associated circuit breaker. These different arrangements lead to different behaviour of the voltage
protection function when a fault occurs. When a tripping command is issued and a circuit breaker is opened,
full voltage remains on the supply side while the load side voltage becomes zero. When voltage supply is
suppressed, undervoltage protection, for instance, will remain picked up. If pickup is to drop out, the current
can be used as an additional criterion for pickup of undervoltage protection (current supervision CS). Under-
voltage pickup can only be maintained when the undervoltage criterion satisfied and a settable minimum
current level (BkrClosed I MIN) are exceeded. Here, the largest of the three phase currents is used. When
the current decreases below the minimum current setting after the circuit breaker has opened, undervoltage
protection drops out.
NOTE
i i
If parameter CURRENT SUPERV. is set to disabled in address 5710, the device picks up immediately
without measurement voltage and the undervoltage protection function in pickup. Apply measuring
voltage or block the voltage protection to continue with configuration. Moreover you have the option of
setting a flag via device operation for blocking the voltage protection. This initiates the reset of the pickup
and device configuration can be resumed.
2.30.2.3

Overvoltage Protection 59 of Side 2

Function
The Overvoltage protection 59 of side 2 function has 2 elements. In case of a high overvoltage, tripping
switch off is performed with a short-time delay, whereas in case of less severe overvoltages, the tripping is
performed with a longer time delay. When one of the adjustable settings is exceeded, the Overvoltage
protection 59 of side 2 function 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 of side 2 elements (= V
428
Selectable Voltage (Param-
eter 616/617)
eter 219)
Vphph (smallest phase-to-
phase voltage)
Vph-n (smallest phase-to-
ground voltage)
V1 (positive sequence
voltage)
Vphph selective (phase-
specific phase-to-phase
voltage)
Vph-n selective (phase-
specific phase-to-ground
voltage)
Vphph (smallest phase-to-
phase voltage)
V1 (positive sequence
voltage)
Vphph selective (phase-
specific phase-to-phase
voltage)
Threshold to be set as
Phase-to-phase voltage
Phase-to-ground voltage
Positive sequence voltage · √3
Phase-specific phase-to-phase pickup
voltage
Phase-specific phase-to-ground pickup
voltage
Phase-to-phase voltage
Positive sequence voltage · √3
Phase-specific phase-to-phase pickup
voltage
/V ) can be set.
dropout value pickup value
SIPROTEC Compact, 7SC80, Manual
E50417-G1140-C486-A8, Edition 07.2017