9424200996 84-43
BE1-11m Settings Calculation Examples
2 =
1
2 = 205
1
60
2 = 6.83
2 =
6.83
2.0
= 3.42
Equation 84-36. 2
nd
Slope (Starting) Pickup Setting
Figure 84-55 shows an example of 2
nd
Slope Restrained Operation.
Figure 84-55. 2
nd
Slope Restrained Operation Example
Based upon good engineering practices during starting mode to overcome dc offset and CT mismatches,
set Restraint Slope 2 % at 1.7 times the running mode slope and add a 25 percent margin. Restraint
Slope 2 % is calculated using Equation 84-37.
2 % = 25% 1 % = 1.7 1.25 0.15% = 32%
Equation 84-37. Restraint Slope 2 %
Set the 2
nd
Slope Pickup (starting) at 3.42 and the Restraint Slope 2% at 32.
Alarm
The BE1-11m provides a Slope % alarm for cases where high loads or through faults cause unbalance in
the differential. The Slope % Alarm is calculated in Equation 84-38.
% = 1.5 2 % = 1.5 32% = 48%
Equation 84-38. Slope % Alarm
The setting range for Slope % Alarm is 50 to 100 in increments of 1, so a Slope % Alarm of 50% is used
for this example.
The Current Differential (87) screen is shown in Figure 84-56.
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