Basler BE1-CDS220, Instruction Manual

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4-6 Protection and Control BE1-CDS220
Table 4-3. Operating Settings for Setting Group Control
Setting Range Purpose Default
Switch Time
1 to 60
0 = Disabled
Time in minutes that determines when a setting
change occurs once the Switch Threshold setting is
exceeded.
0
Switch
Threshold
0 to 150
Percentage of the SG0 Monitor Setting that must be
exceeded for a setting group change to occur.
0
Return Time
1 to 60
0 = Disabled
Time in minutes that determines when a return to SG0
will occur once the monitored current has decreased
below the Return Threshold setting.
0
Return
Threshold
0 to 150
Percentage of the SG0 Monitor Setting that the
monitored current must decrease below in order for a
return to SG0.
0
Monitor Setting
x51P, x51N,
x51Q
Determines when automatic setting group changes
occur. Time overcurrent elements x51P, x51N, or
x51Q can be selected so that setting group changes
are based on load current.
Note: x = none, 1, or 2.
51P
Setting Group
Change (SGC)
Alarm Timer
1 to 10
0 = Disabled
Measured in seconds, the SGC alarm timer sets the
amount of time the alarm is on.
5
Automatic control of the active setting group allows the relay to automatically change configuration for
optimum protection based on the current system conditions. For example, in locations where seasonal
variations can cause large variations in loading, the overcurrent protection can be set with sensitive
settings during the majority of the time and switch to a setting group with lower sensitivity (higher pickups)
during the few days of the year when the loading is at peak.
There are five settings for each group that are used for automatic control. Each group has a switch to
threshold and time delay, a return threshold and time delay and a monitored element. The switch to and
return thresholds are a percentage of the SG0 pickup setting for the monitored element. The monitored
element can be any of the 51 protective functions. Thus, if you wish to switch settings based upon
loading, you could set it to monitor 51P. If you wish to switch settings based upon unbalance, you could
set it to monitor 51N or 51Q. When the monitored element is 51P, any one phase must be above the
switch to threshold for the switch to time delay for the criteria to be met. All phases must be below the
return threshold for the return time delay for the return criteria to be met.
Figure 4-6 shows an example of using the automatic setting group selection settings to change settings
groups based upon loading. Note that the AUTO input must be at a TRUE logic state in order to allow the
automatic logic to operate. At time = 0, current begins to increase. When current reaches 75 percent of
pickup, Setting Group 2 begins timing (30 minutes). When current reaches 90 percent of pickup, Setting
Group 3 begins timing (5 minutes). After 5 minutes, at time = 37, with the current still above Setting Group
3 threshold, Setting Group 3 becomes active and the setting group change output pulses. At time = 55,
Setting Group 2 timer times out but no setting group change occurs because a higher setting group takes
precedence. The faint dashed line for SG2, between time = 55 and 75 shows that Setting Group 2 would
be active except for Setting Group 3. Current decreases to 75 percent at time = 70 and Setting Group 3
return timer begins timing. Current varies but stays below 75 percent for 5 minutes and at time = 75,
Setting Group 2 becomes active and the setting change output pulses. After 20 minutes, Setting Group 0
becomes active and the setting change output pulses.