Basler Electric BE1-700 - Manual (Page 206)

settings and equations generated as a result of the selections made through the Windows based
BESTCOMS interface program. The user can see the protection and control elements that are enabled
(set to mode 1) for this application and see how the elements are logically wired together (Boolean
equations). If the user should decide to build on this scheme, all elements required for a modified
application are available in BESTCOMS. For programming details, refer to Section 7, BESTlogic
Programmable Logic and Section 14, BESTCOMS.
Protection Elements
Setting a protection element =s pickup at zero will disable the element. To see which elements are
enabled, select the System Setup Summary Screen in BESTCOMS and note the color of the dot
associated with each protection element. (Refer to the color legend on the System Setup Summary
Screen.) Each protection element in this preprogrammed logic scheme should be yellow or green
depending on whether an operational setting has been applied.
To ensure that voltage and frequency at the bus are maintained within the limits, two over/undervoltage
elements (59P-159P/27P-127P), one phase sequence check (negative-sequence voltage (47)), six
over/underfrequency elements (81o/u
Y581o/u) and one volts/hertz element (24) are provided.
Dead Line Reclosing (Conditional Voltage Reclose)
With a source of generation on the feeder, provision for up to four dead line (conditional voltage) recloses
are provided in this logic scheme. With the reclose fail time set to zero, the Reclose Output (79C) is held
indefinitely and Output 3 (Out3) effectively becomes a dead line reclosing contact. A sync-check element
is included in this scheme for network applications requiring angle comparison between two voltages
(either side of an open breaker) before allowing the breaker to reclose. The logic settings in Table 8-20
include the logic equations that connect the various elements (electronic wiring) of the of the VF
protection scheme. Figures 8-8 and 8-9 shows the logic drawings for the preprogrammed VF protection
scheme. Note that all voltage and frequency trips are connected to VO2 which, in turn, operates Output 2.
Output 3 is used for automatic reclosing of the circuit breaker.
Input 3 is used for external initiate of reclosing; Input 2 is connected to an external reclosing on/off switch
defeating automatic reclosing when in the OFF position. And Input 1 provides breaker position/status to
the logic scheme.
Alarms
Three logic variables drive the front panel LEDs: Relay Trouble (ALMREL), Major Alarm (ALMMAJ) and
Minor Alarm (ALMMIN). A fourth logic variable, Logic Alarm (ALMLGC), has no associated front panel
LED. When the relay self-test detects a problem in the relay (ALMREL) as programmed for the OC & V
protection scheme, the Relay Trouble LED lights, Output A operates and all other outputs are disabled.
When a major or minor alarm is detected, the associated LED lights. If the user chooses, Output A can
also be set to operate for a major or a minor alarm.
NOTE
Tables 8-16 through Table 8-19 provide detailed logic definitions for the inputs,
outputs, protection and control elements. All inputs, logic blocks, and outputs
available for use in the preprogrammed logic are described in the following
tables.
8-24 BE1-700 Application 9376700990 Rev M