Settings - Siemens SIPROTEC 7SJ62 Manual

Grounded System
In grounded systems, a value is set below the minimum anticipated ground fault current. It is important to note
that 3I0 DIR (current value RELEASE DIRECT.) only detects the current components that are perpendicular
to the directional limit lines defined at addresses 3124 and 3125. COS ϕ is the method of measurement used,
and the correction angle is set to –45°, since the ground fault current is typically resistive-inductive (right section
of Figure 2-78 "Directional curve for cos-ϕ-measurement" in the functional description of the sensitive ground
fault detection).
Electrical Machines
One may set the value COS ϕ for the measurement method and use a correction angle of +45° for electrical
motors supplied from a busbar in an ungrounded system, since the ground current is often composed of an
overlap of the capacitive ground current from the system and the resistive current of the load resistance (left
part of Figure "Directional characteristic for cos-ϕ-measurement" in the functional description of the sensitive
ground fault detection).
Information on the Configuration of the Current Threshold
With devices with sensitive ground fault input, generally settings may be entered in primary values with consid-
eration given to the ratio of the applicable current transformer. However, problems related to the resolution of
the pickup currents can occur when very small settings and small nominal primary currents are involved. The
user is therefore encouraged to enter settings for the sensitive ground fault detection in secondary values.
2.12.5

Settings

Addresses which have an appended "A" can only be changed with DIGSI, under "Display Additional Settings".
The table indicates region-specific default settings. Column C (configuration) indicates the corresponding sec-
ondary nominal current of the current transformer.
Addr. Parameter
3101 Sens. Gnd Fault
3102 CT Err. I1
3102 CT Err. I1
3103 CT Err. F1
3104 CT Err. I2
3104 CT Err. I2
3105 CT Err. F2
3106 VPH MIN
3107 VPH MAX
SIPROTEC, 7SJ62/64, Manual
C53000-G1140-C207-2, Release date 01.2008
C Setting Options
OFF
ON
ON with GF log
Alarm Only
0.001 .. 1.600 A
1A 0.05 .. 35.00 A
5A 0.25 .. 175.00 A
0.0 .. 5.0 °
0.001 .. 1.600 A
1A 0.05 .. 35.00 A
5A 0.25 .. 175.00 A
0.0 .. 5.0 °
10 .. 100 V
10 .. 100 V
2.12 Ground Fault Protection 64, 67N(s), 50N(s), 51N(s)
Default Setting
OFF (Sensitive) Ground Fault
0.050 A Current I1 for CT Angle
Error
1.00 A Current I1 for CT Angle
Error
5.00 A
0.0 ° CT Angle Error at I1
1.000 A Current I2 for CT Angle
Error
10.00 A Current I2 for CT Angle
Error
50.00 A
0.0 ° CT Angle Error at I2
40 V L-Gnd Voltage of Faulted
Phase Vph Min
75 V L-Gnd Voltage of Unfault-
ed Phase Vph Max
Functions
Comments
239