The iSMA-B-AAC20 controllers have a service that allows recording events / alarms. Alarms can be generated off the NV-type components only. Alarms can be recorded only on the SD card. By default, the device is not equipped with an SD card. In order to use the alarm service, SD card should be installed. When an extension of the alarm is created, the database file is created on the SD card. The device stores up to 2500 alarm events. If this number is exceeded, the new event will overwrite the oldest records.
To add an extension to the component alarm you must select an appropriate option in the Alarm slot (Change Of State for Boolean components, and Out Of Range for Numeric components). After changing and saving the settings, an alarm extension is created under the component, where all the settings associated with the process of generating an alarm event can be adjusted.
The history service is a component, which is responsible for writing historical values in the microSD memory. The history service is available in the iSMA_controlApi kit palette and the component must be placed under the service folder.
After any historical extension is added on the NV component, a historical database will be created under the history service component in order to store NV points of historical components.