L-DALI User Manual
134
LOYTEC
Version 5.2
LOYTEC electronics GmbH
underlying BACnet objects are enabled. Alarm conditions can be specified for analog input,
output, value objects (AI, AO, AV), for binary input, output, value objects (BI, BO, BV),
and for multi-state input, output, value objects (MSI, MSO, MSV). With BACnet intrinsic
reporting alarm conditions on binary output (BO) and multi-state output (MSO) can only be
feedback alarms.. These restrictions do not apply, if the alarm condition reports to a generic
alarm server.
Alarm servers in the BACnet technology are mapped to BACnet Notification Class (NC)
objects. Each alarm server is mapped to one NC. The notification class number can be
configured in the object instance number property of the alarm server object.
Remote alarms in the BACnet technology refer to a remote NC object. When the device
starts up, the remote alarm object reads out the current alarm state of the remote NC and
reporting objects. To get notified about alarm transitions during run-time, the device
registers in the Recipient_List of the remote NC object.
Some BACnet devices do not send a usable text in their alarm notification messages. For
those devices the alarm client provides the option
Ignore alarm message text
. If this option
is enabled, the alarm client ignores the message text of an alarm notification and reads the
description property of the alarmed object instead.
6.6.3 BACnet Schedulers and Calendars
BACnet schedulers and the BACnet calendar adhere to the standard schedule and calendar
object in BACnet. For each scheduler a BACnet Schedule object is created. The calendar
deserves a closer look. For each calendar pattern a BACnet Calendar object is created. The
visible calendar on the Web UI is therefore a collection of BACnet calendar objects. Each
calendar pattern therefore is associated with a BACnet object instance number. The
calendar pattern “Holidays” is for example visible as CAL,1 on the BACnet port.
The BACnet schedule object allows only objects of one selected data type to be scheduled.
Therefore, schedulers on BACnet can only schedule one class of data points (e.g., only one
group of analog data points). As a consequence, the value preset in BACnet always has only
one element. The name of the value preset is not stored in BACnet. It is not accessible over
the BACnet network, either. Therefore, a default name is created, such as ‘22 °C’ for an
analog value. An example of two scheduled BACnet objects is shown in Figure 121. With
the extended BACnet features enabled in the project settings, a preset label can be assigned
to a specific scheduled value. For example the value ’16 °C’ can be assigned ‘night’. Click
in the column header and type the desired text.
Figure 121: Example value presets in BACnet schedulers.
Priorities of exception days in a BACnet scheduler range from 1 (the highest) to 16 (the
lowest). Weekdays in BACnet have no priority.
Changing the number of calendar patterns in a BACnet calendar can only be done through
the configuration software and not during run-time. The individual calendar pattern entries
in the calendar patterns can be changed at run-time. Therefore, it is advisable to reserve a
suitable number of calendar patterns in a BACnet calendar and leave them empty if not
needed immediately.
6.6.4 BACnet Trend Logs
Trending in the BACnet technology is based on the BACnet TrendLog object. A number of
restrictions apply to trend log objects in BACnet. Trend log objects must be created by the
