Typical Application - Basler BE1-11g Instruction Manual

138
Setting
Mode
Directional Supervision
Angle
Diameter 1
Diameter 2
Offset 1 & 2
Time Delay 1 & 2
Voltage Pickup 1 & 2
Voltage Time Delay 1 & 2

Typical Application

Settings and measurements are used to determine if the measured system impedance is within the
tripping criteria to indicate loss of excitation.
This consists of two mho circles with the lower edge offset from the R axis by an equal distance typically
set to 1.1*Xd. The diameter of the smaller circle (Z1) is typically set so that the upper edge is located at
X'd/2 below the R axis. The larger circle (Z2) and the directional blocking are both set to coordinate with
the steady-state stability limit of the generator. The larger circle has a time delay to prevent nuisance
tripping. Refer to Figure 87.
Z2 Diameter
Loss of Excitation - Impedance Based (40Z) Protection
Table 51. Operational Settings
Range
Disabled, Non-Voltage Control,
Voltage Control, or Both
–90 to 0
0.1 to 100 (5A CTs)
0.5 to 500 (1A CTs)
0.1 to 100 (5A CTs)
0.5 to 500 (1A CTs)
0 to 110 (5A CTs)
0 to 550 (1A CTs)
0 to 300,000
0 or 5 to 180
0 to 300,000
X
Offset
Figure 87. Typical Application
9424200994 Rev N
Unit of
Increment
Measure
n/a n/a
0.1 degrees
0.1 ohms
0.1 ohms
0.1 ohms
varies milliseconds
1 volts
varies milliseconds
R
Blinder Angle
Z1 Diameter
P0037-02
01-16-06
Default
Disabled
–15
1
1.4
1.1
0
0
0
BE1-11g