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Communication-capable Circuit Breakers
WL Circuit Breaker
Setpoints
In addition to the load management
option (load shedding/load restore),
the metering modules offer an
option for an automatic monitoring
of operating data and the
generation of an alarm.
Two setpoints can be defined (e.g.
for overvoltage). With the lower
setpoint, an alarm can be generated
via the setpoint value (e.g. > 410V),
whereas, with a voltage increase, a
tripping event (e.g. > 430V) can be
generated.
Minimum for Communicated
Currents
In order to avoid the detection,
display and communication of very
low currents generated by system
noise, even with the circuit breaker
in the disconnect position, the
"Minimum for Communicated
Currents" parameter offers the
option of setting all detected
current values smaller than this
parameter to zero. The factory
setting is 50A. This means that
all values smaller than 50A are
displayed as "0" on the display,
interpreted as "0" for internal
calculations (power) and also
transmitted as "0" via the
communications. If this parameter
is changed to "0", this function is
deactivated and all detected current
measuring values will be directly
used.
The parameter can be found in the
parameter tree of the BDA.
Normal Positive Power Flow
Direction
The current direction of the energy
"flow" and the question, "How much
energy has, up to now, flowed in
both directions?" is of particular
interest for tie breaker applications.
For a determination, it is important
to define a "normal direction." This
direction can either be "from top to
bottom" or "from bottom to top."
2/19
The measured real power is either
assigned to a positive polarity (in
normal direction) or a negative
polarity (opposite normal direction).
In contrast, the measured currents
are always assigned a positive
polarity.
With energy, the transmitted
energy values are incorporated
in two counters, real energy and
real energy opposite to normal
direction. The two energy counters
are not assigned a polarity.
Event and Trip Log
All events (except for tripping
events) are labeled with a time
stamp and an ON (+) or OFF (-)
indication and entered in the
event log.
The event log has a depth of 10
events and works like a FiFo
memory (first in, first out), i.e.
the oldest event is deleted from
the event log upon the occurrence
of a new event.
Figure
In the event log the last 10 events on the
2-9
contains the last 5 trips. Both of them can be displayed with the BDA.
WL PROFIBUS Communication and Electronic Accessories • July 2004
The trip log is similar to the event
log, however, only the last 5 trips
are recorded with a time stamp
and entered in the trip log.
Note: The event and the trip log
are only available with the COM15
module.
CubicleBUS
are listed. The trip log
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