Basler BE1-CDS220, Instruction Manual

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4-2 Protection and Control BE1-CDS220
The setting group control function has four logic variable outputs, SG0, SG1, SG2, and SG3. The
appropriate variable is asserted when each setting group is active. These logic variables can be used in
programmable logic to modify the logic based upon which setting group is active. For example, it may be
desired for the 51P to trip the low side breaker through OUT2 under normal conditions, but to trip the 86T
lockout relay through OUT1 when in Setting Group 3. The logic for OUT1 would include the term
51PT
∗
SG3 so that 51PT only actuates OUT1 when SG3 is asserted.
The setting group control function also has an alarm output variable SGC (Setting Group Changed). This
output is asserted whenever the relay switches from one setting group to another. The SGC alarm bit is
asserted for the SGCON time setting. This output can be used in the programmable alarms function if it is
desired to monitor when the relay changes to a new setting group. See Section 6, Reporting and Alarm
Functions, Alarms Function, for more information on using alarm outputs.
The SGCON time setting also serves to provide anti-pump protection to prevent excessive changing
between groups. Once a change in active group has been made, another change cannot take place for
two times the SGCON setting.
When the relay switches to a new setting group, all functions are reset and initialized with the new
operating parameters. The setting change occurs instantaneously so at no time is the relay off line. The
active setting group is saved in nonvolatile memory so that the relay will power up using the same setting
group as it was using when it was powered down. To prevent the relay from changing settings while a
fault condition is in process, setting group changes are blocked when the relay is in a picked-up state.
Since the relay is completely programmable, the fault condition is defined by the pickup logic expression
in the fault reporting functions. See Section 6, Reporting and Alarm Functions, Fault Reporting, for more
information.
The selection of the active setting group provided by this function block can also be overridden. When the
logic override is used, a setting group is made active and the relay stays in that group regardless of the
state of the automatic or manual logic control conditions.
BESTlogic Settings for Setting Group Control
BESTlogic settings are made from the BESTlogic Function Element screen in BESTCOMS. The
BESTCOMS screen used to select BESTlogic settings for the Setting Group Selection function is
illustrated in Figure 4-2. To open the BESTlogic Function Element screen for Setting Group Selection,
select Setting Group Selection from the Screens pull-down menu. Then select the BESTlogic button in the
lower left hand corner of the screen. Alternately, settings may be made using the SL-GROUP ASCII
command.
Figure 4-2. BESTlogic Function Element Screen, Setting Group Selection