### BACnet Alarm The information below provides a FULL description of this microblock and all of its properties. What information you see and what you can do with it depends on your license and the application you are in, and in some cases, a controller's driver version.
Microblock family | Log microblocks
Icon and symbol |
What it does | This microblock transmits alarms and supplemental data from the control program to the system's alarm management system. An alarm generated by this microblock is time-stamped with the time the alarm was generated. For the system to receive an alarm, the Potential alarm source field must be checked. The color square on the left side of the microblock indicates the microblock's status: Red = In alarm Gray = Not in alarm Black = Potential alarm source field is unchecked
Click for details below Properties Alarms Tips and tricks
#### Properties TIPS Alt+click any value in the WebCTRL® or Field Assistant interface to view property details, including its editing privilege and expression (location path) for use on graphics. You can right-click some properties in the EIKON® Property Editor and select Make editable or Make read-only to determine that property's functionality in your system.
Display Name | The microblock label used in the EIKON® application and the WebCTRL® interface. You can use any characters except the " character.
Reference Name RefName | Use the default reference name unless you want a more descriptive name for graphics or network links. Limitations: lower case only limited to 40 characters cannot begin with a number must be unique within a control program
Description | (optional) A BACnet-visible microblock description.
Lock Present Value | Check to output the locked value from the microblock instead of the microblock's calculated value.
Editing Privilege | Preset - Each microblock property has an appropriate privilege or role assigned to it. You can use Global Modify in the WebCTRL® interface to find out what the actual privilege is. CAUTION If you change the Editing Privilege from Preset, the privilege you select will be used for all properties of this microblock, which is not always desirable.
Inactive Text | The text the system displays when the microblock's input is off (false).
Active Text | The text the system displays when the microblock's input is on (true).
Minimum off time | The minimum period (seconds) that the microblock's present value will be off, regardless of the input signal to the microblock.
Minimum on time | The minimum period (seconds) that the microblock's present value will be on, regardless of the input signal to the microblock.
BACnet Configuration
Network Visible | Check to allow other BACnet equipment to read the microblock's present value. Must be checked for this microblock to generate alarms.
Object Instance | Auto-assign - A BACnet Object ID is assigned by the system. Use specific value - (0–3999999) Assign a number that is unique within the controller.
Property Page Text
Show Property Page Text | Check to show this microblock's value on the equipment's Properties page.
Property Page Text | You can edit the microblock description that appears on the Properties page. See "Editing Properties page text using special characters" and "Formatting a microblock property" in EIKON® Help.
#### Alarms
Potential alarm source | Check to make this microblock available in the system's Alarm Sources list.
Critical | Determines the color of the system-wide alarm button when the alarm comes in if the alarm's Template field is set to Universal. = Critical = Non-critical
Category | The category you want to use to filter this microblock's alarms on the system's Alarms page > View tab.
Template | Universal - Allows your system to use the Alarm text and Return text defined in the microblock, and the Critical checkbox to determine the color of the system-wide alarm button when the alarm comes in.
Alarm
Alarm Enabled | Check to send a message when this microblock indicates an alarm condition.
Delay Seconds | The time the microblock's present value must remain in an alarm condition before the microblock sends an alarm.
Alarm text | The message displayed on the WebCTRL® Alarms page > View tab when an alarm condition occurs. A relative path is useful for alarm messages that you will reuse in multiple WebCTRL® locations because the path is relative to the item that contains the path.
Alarm requires acknowledge | Check to require that an operator acknowledge alarm notifications on the system's Alarms page > View tab.
Return to Normal
Return Enabled | Check to send a message when an alarm condition has returned to normal.
Return text | The message displayed on the WebCTRL® Alarms page > View tab when an alarm condition returns to normal. A relative path is useful for alarm messages that you will reuse in multiple WebCTRL® locations because the path is relative to the item that contains the path.
Return requires acknowledge | Check to require that an operator acknowledge return-to-normal notifications on the system's Alarms page > View tab.
Fault
Fault Enabled | Check to send a message when a fault condition occurs, such as a misconfigured or non-existent sensor.
#### Tips and tricks You can add a field code to the alarm text that will retrieve the value of another microblock at the time the alarm is triggered. Add the field code`$source:<path>$`, substituting <path> with the path to the value you want. The path can be an absolute path or a path relative to the BACnet Alarm microblock. See Defining WebCTRL® paths in WebCTRL® Help. Example of alarm text: The conference room is hot. The temperature is $source:/trees/geographic/rd_facility/zone_1/lstat/present_value$ NOTE Field codes are processed when an alarm is processed at the server, not when the alarm is triggered in the controller. For slow changing values on a fast network, this is almost equivalent to the latched data feature in a legacy system. The value 2 to 3 seconds after the alarm occurred will be very close to the value at the time of the alarm. But for fast changing values on a slow network, the value could be misleading. If the alarm is processed up to a minute or two after the alarm occurred, the value could be very different than the value at the time of the alarm.