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Digital point description
The list below defines the digital-input
points in the RCU.
Digital points are identified by Digital_Point
IDentity or D_PID.
The following data is given for each point.
D_PID: the identifier for this point
including a phase identifier if valid.
Source: the source of the data, namely
the RCU or the Fusesaver.
The valid states, such as open/close
The source of the event time tag (if the
point generates events), which may be
the RCU itself or the Fusesaver.
How the status is determined.
How events are determined.
How the status is set on restart of the
RCU.
Data qualifiers which are supported for
that point.
Some digital points behave like protection
relay flags; they are set by a particular
protection event.
These flag points can be cleared by the
SCADA operator sending "Clear Flags"
control.
They can also be set to be cleared
automatically after the passing of a set time
period, for example, one hour.
These points are:
Protection flags
Digital
point
Use
D_PID
17, 18,
Indicates permanent fault on the line,
19
which the Fusesaver could not clear
20, 21,
Indicates transient fault on the line,
22
which was cleared by the Fusesaver
Indicates a fault current was detected
23, 24,
but ended before the Fusesaver tripped.
25
For example, a downstream transformer
fuse may have cleared the fault.
54, 55,
Indicates a very short-lived current
56
surge -possibly due to lightning activity.
Table 11: Protection flags
See Table 15: RCU database digital points
list for a full list of all digital points available
in pages 20-29.
Analog point description
The list below defines the analog-input
points in the RCU.
Analog points are identified by Analog_Point
Identity or A_PID.
The following data is given for each point:
A_PID: the identifier for this point
including nominating the relevant phase
if valid.
Source: the source of the data, namely
the RCU or the Fusesaver.
The engineering units, range and
resolution.
The source of the event time tag (if the
point generates events), which may be
the RCU itself or the Fusesaver.
A description of the data.
What happens on restart of the RCU.
Data qualifiers, which are supported for
that point.
See Table 16: RCU database analog points
list for a full list of all analog points available
in pages 30-32.
Events and deadbands
Some analog points generate events on
change of value controlled by their
deadband. Other points do not generate
events on change of value, refer to Table 16:
RCU database analog points list for Analog
points on page 30.
As an example, DNP3 points can be
configured to belong for class 1, 2 or 3,
which will mean they will generate DNP3
protocol events if they have that capability
or alternatively they may be set to class 0,
which do not generate DNP3 protocol
events.
Deadbands are fixed for most points (a
deadband is the value by which a point
must change in order for it to generate an
event). However, the deadband can be
configured for some points so that the
utility can control the bandwidth used.
17
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