Basler BE1-11g Instruction Manual page 618

606
Basler Electric time current characteristics are determined by a linear mathematical equation. The
induction disk of an electromechanical relay has a certain degree of non-linearity due to inertial and
friction effects. For this reason, even though every effort has been made to provide characteristic curves
with minimum deviation from the published electromechanical curves, slight deviations can exist between
them.
In applications where the time coordination between curves is extremely close, we recommend that you
choose the optimal time dial setting by inspection of the coordination study. In applications where
coordination is tight, it is recommended that you retrofit your circuits with Basler Electric protection
systems to ensure high timing accuracy.
Equivalent
Curve
To
S1 ABB CO-2
S2
GE IAC-55
I1 ABB CO-8
I2 GE IAC-51
M
ABB CO-7
L1 ABB CO-5
L2
GE IAC-66
V1 ABB CO-9
V2 GE IAC-53
E1
ABB CO-11
E2 GE IAC-77
D ABB CO-6
The 46 Curve
The 46 curve (Figure 377) is a special curve designed to emulate the (I
generators using what is frequently referred to as the generator K factor.
The 46 Curve Characteristics
46 Pickup Current
Generators have a maximum continuous rating for negative sequence current. This is typically expressed
as a percent of stator rating. When using the 46 curve, the user should convert the continuous I
data to actual secondary current at the BE1-11g. This value (plus some margin, if appropriate) should be
entered as the pickup setting. For example, if a generator's rated full-load current is 5 amperes, a pu
setting of 0.5 A would allow 10% continuous I
46 Time Dial (= Generator K factor)
The amount of time that a generator can withstand a given level of unbalance is defined by Equation 37.
The K factor gives the time that a generator can withstand 1 per unit negative sequence current. For
example, with a K factor of 20, since (I
the condition for 20 seconds. Typical values for generator K factors are in the 2 to 40 range. The BE1-11g
Time Curve Characteristics
Table 258. Time Dial Setting Cross-Reference
Electromechanical Relay Time Dial Setting
0.5 1.0 2.0 3.0
Basler Electric Equivalent Time Dial Setting
0.3 0.8 1.7 2.4
0.2 1.0 2.0 3.1
0.3 0.7 1.5 2.3
0.6 1.0 1.9 2.7
0.4 0.8 1.7 2.5
0.4 0.8 1.5 2.3
0.4 0.9 1.8 2.7
0.3 0.7 1.4 2.1
0.4 0.8 1.6 2.4
0.3 0.7 1.5 2.4
0.5 1.0 1.9 2.7
0.5 1.1 2.0 2.9
.
2
���� =
( ����
Equation 37
2
) becomes 1 at 1 per unit of current, the generator can withstand
2
4.0 5.0 6.0 7.0
3.4 4.2 5.0 5.8
4.0 4.9 6.1 7.2
3.2 4.0 5.0 5.8
3.7 4.8 5.7 6.8
3.3 4.3 5.3 6.1
3.3 4.2 5.0 6.0
3.9 4.9 6.3 7.2
3.0 3.9 4.8 5.7
3.4 4.3 5.1 6.3
3.2 4.2 5.0 5.7
3.5 4.3 5.2 6.2
3.7 4.5 5.0 5.9
2
) t withstand ratings of
2
����
)
2
2
9424200994 Rev U
8.0 9.0 10.0 11.0
6.7 7.7 8.6 9.7
8.1 8.9 9.8 n/a
6.8 7.6 8.7 n/a
8.0 9.3 n/a n/a
7.0 8.0 9.0 9.8
7.0 7.8 8.8 9.9
8.5 9.7 n/a n/a
6.7 7.8 8.7 9.6
7.2 8.4 9.6 n/a
6.6 7.8 8.5 n/a
7.4 8.2 9.9 n/a
7.2 8.0 8.9 n/a
2
rating
BE1-11g