L-VIS User Manual
159
LOYTEC
Version 6.2
LOYTEC electronics GmbH
9.11 Alarm Generators
The alarm generator object is used to monitor input data points and issue alarms based on
rules which are set on the
Alarm Generator
property page. For a discussion of alarming on
L-VIS devices in conjunction with the underlying network technology and system wide
alarms, please also refer to sections 10.3.1 and 10.11 of this manual.
To add a new alarm generator, use the context menu of a collection object in the object tree
and select ‘Add Alarm Generator’. A new alarm generator object will be created and
connected to the collection object.
Once the alarm generator object is created, connect the input data points which should be
monitored. Each of the connected input data points will show up on the alarm generators
property page, where the monitoring rules can be defined.
NOTE:
It is sometimes useful to connect the same input data point twice or more times to the same
alarm generator, when the desired alarm conditions are too complex to cover in one rule,
for example different rules for alarm set and alarm clear or multiple non-overlapping value
ranges which should trigger an alarm. In this case, assign different names to the connected
data points on the General property page, so that you may distinguish between them later.
Once the required input data points are connected, the alarm generator needs one output
data point to which the result should be written. The desired output data point must be
connected before the alarm generator can be configured, because the type of data point
determines the configuration options. The following data point types may be used as
outputs for the alarm generator:
Alarm Server:
On CEA-709 devices, a local alarm server data point may be
connected to deliver the alarm to remote alarm clients and display the alarm on
an alarm list control. The alarm server keeps record of all pending alarms,
delivers them to any connected clients and manages acknowledgement of alarms.
Scalar Value:
Any data point representing a single scalar value, for example a
register. In this case, the alarm generator uses the connected data point as a
Boolean value, setting it to either 0 (OFF) or 1 (ON). Using the data points
scaling factors, this Boolean value may be translated into any two values, one to
signal ‘alarm clear’ and one for ‘alarm set’. This is most useful if the generated
alarm is to be processed further or displayed on the L-VIS device, for example to
trigger actions or display warning messages.
Multi-State Value:
Similar to a scalar value, but the alarm generator can be
configured to set the output to any of the available states, which can be selected
easily from a dropdown box. Useful on BACnet devices, where a multi-state
point may be used to signal a number of different alarm conditions.
SNVT_switch:
Available on CEA-709 devices, a data point representing an
entire switch variable may be connected. In this case, the alarm generator sets
both value and state of the connected switch to either ON/100 or OFF/0. Useful
in cases where the generated alarm is to be processed by a remote device which
uses one switch input for each alarm.
SNVT_alarm2:
Available on CEA-709 models, a data point representing a
SNVT_alarm2 structured NV may be connected. In this case, the user may set all
elements of the alarm2 structure to the desired values, including the alarm
priority and a description. This is most useful to communicate the result to a
remote device which provides a compatible alarm input variable.
