Basler BE1-CDS220, Instruction Manual

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BE1-CDS220 BESTCOMS Software 14-13
Diff Alarm
The Diff Alarm tab (Figure 14-16) brings up a screen that allows setting the percentage of differential
characteristic. The default value is 67% but the permissible range is 50 to 100.
Figure 14-16. Percentage Differential Screen, Diff Alarm Tab
Overcurrent Protection
Pull down the Screens menu and select Overcurrent or click on the Overcurrent Protection icon
that is shown at the right margin of this paragraph. This screen has six folder tabs and the first
tab is 51.
51
This screen (Figure 14-17) allows you to enter the settings for the 51 time overcurrent elements. BE1-
CDS220 relays have three phase time overcurrent elements, three neutral time overcurrent elements, and
three negative-sequence time overcurrent elements. They are divided up into three tabs, (51, 151, and
251). The pull down Pickup menu allows you to select the relative pickup quantity. BE1-CDS220 relays
measure the current input in secondary amperes. If you want to use per unit, percent amperes, or primary
current, you must coordinate the settings in Power Systems & Conversions. Settings for Time Dial and
Curve (time characteristic curve) are conventional settings. If you want to change the characteristic curve
constants, select the Curve Coefficients and a dialog box opens for those entries. Select the BESTlogic
button at the bottom of the Phase (51P) panel. The status of the logic is shown above the BESTlogic
button. A dialog box (BESTlogic Function Element) opens showing the status of the element logic and the
logic scheme name. If you have a custom logic scheme active, you may change the status of the element
logic by pulling down the menu and selecting from the available choices.