Basler Electric BE1-11t - Manual (Page 141)

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Figure 91. Input Control Binary Inputs
CT Source
The CT Source setting configures the setting group selection function to monitor CT circuit 1 or CT circuit
2. CT circuit 1 terminals are designated D1 (IA1) through D8 (IG1) and CT circuit 2 terminals are
designated F1 (IA2) through F8 (IG2). For an illustration, refer to the
Terminals and Connectors chapter.
Alarm and Timer
The setting group selection function logic also has an alarm output variable called Setting Change
(Setting Group Changed). This output is asserted whenever the BE1-11t switches from one setting group
to another. The Setting Change 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 BE1-11t changes to a new
setting group. See the
Alarms chapter for more information on setting up alarms.
The SGCON time setting also serves to provide anti-pump protection to prevent excessive changing
between groups. Once a change in the active group has been made, another change cannot take place
for two times the SGCON setting.
The SGC Active (Setting Group Change Active) alarm output is typically used to provide an external
acknowledgment that a setting group change has occurred. If SCADA (Supervisory Control and Data
Acquisition) is used to change the active group, then this signal could be monitored to verify that the
operation occurred. The SGC Active alarm output ON time is user programmable and should be set
greater than the SCADA scan rate. This can be set through BESTCOMSPlus.
Automatic Setting Group Selection
The setting group element has the built-in ability to automatically change setting groups. One method is
based on the history of the current sensed by the BE1-11t. Another method is based upon the status of
the fuse loss logic (60FL). To enable automatic change of setting groups, setting group selection must be
enabled and the AUTOMATIC input must be logic 1.
When automatic selection is enabled, it holds precedence over all manual logic control.
The automatic setting group selection can be used to force the BE1-11t to change to settings that will
automatically compensate for cold-load pickup conditions. For instance, if the BE1-11t senses current
drop below a very small threshold for a period of time indicating an open breaker, then the BE1-11t will
move to an alternate setting group that will allow for the large inrush of current the next time the load is
energized. After current has returned to measurable levels for some period of time, the BE1-11t returns to
the normal settings. Another application is to prevent the BE1-11t from seeing an overload condition as a
fault. If the BE1-11t sees sustained high level phase or unbalance currents that are encroaching on
normal trip levels (indicative of an overload or load imbalance rather than a fault), the BE1-11t will move
P0037-44
05-03-06
D3
D2
D1
D0
AUTO
SG3
SG2
SG1
SG0
SGC
BE1-11t Setting Groups