Basler BE1-CDS220, Instruction Manual

Page: 78 / 476

4-12 Protection and Control BE1-CDS220
An alarm variable is also provided in the programmable alarms function that can be used to indicate an
alarm condition if the percentage restrained differential protection is nearing a trip condition on load. This
alarm triggers a diagnostic routine that attempts to determine the source of the mismatch that is causing
the differential unbalance. See Section 6, Reporting and Alarm Functions, Alarms Function, for more
details on the alarm reporting function.
BESTlogic Settings for Phase Differential
BESTlogic settings are made from the BESTlogic Function Element screen in BESTCOMS. Figure 4-11
illustrates the BESTCOMS screen used to select BESTlogic settings for the 87 function. To open the
BESTlogic Function Element screen, select Percentage Differential from the Screens pull-down menu.
Then select the 87 Phase tab. Open the BESTlogic Function Element screen by selecting the BESTlogic
button. Alternately, these settings can be made using the SL-87 ASCII command.
Figure 4-11. BESTlogic Function Element Screen, Phase (87)
At the top center of the BESTlogic Function Element screen is a pull-down menu labeled Logic. This
menu allows viewing of the BESTlogic settings for each preprogrammed logic scheme. A custom logic
scheme must be created and selected in the Logic pull-down menu at the top of the screen before
BESTlogic settings can be changed. See Section 7, BESTlogic Programmable Logic.
Enable the 87 function by selecting its mode of operation from the Mode pull-down menu. To connect the
element's input, select the button for the input in the BESTlogic Function Element screen. The BESTlogic
Expression Builder screen will open. Select the expression type to be used. Then, select the BESTlogic
variable, or series of variables to be connected to the input. Select Save when finished to return to the
BESTlogic Function Element screen. For more details on the BESTlogic Expression Builder, see Section
7, BESTlogic Programmable Logic. Select Done when the settings have been completely edited.
Table 4-4 summarizes the BESTlogic settings for Phase Differential.
Table 4-4. BESTlogic Settings for Phase Differential
Function Range/Purpose Default
Mode
0 = disabled
1 = enabled
1
BLK Logic expression that disables function when TRUE. 0