The iSMA-B-AAC20 controller supports 3 types of BACnet data points:
- AnalogValue: to read/write the numeric values;
- BinaryValue: to read/write the Boolean values;
- MultiState: to read/write the integer and multistate values.
BACnet Object Integration (Link Back Forward)
In some cases there is a need to synchronize the BACnet data from different sources such as the LCD display or the Modbus network. To do so in the iSMA-B-AAC20 controller a special mechanism called link back forward needs to be used. This mechanism requires to use the NV component without connected In slot and in auto mode. The NV component Out slot must be connected to one of the input slots in the BACnet object, and the BACnet data point component must have the slot Link Set in true state. Now, when the input slot of the BACnet data point, which is connected to the NV component, will be changed from the BACnet protocol level, “Link back forward” action will be executed, and the value of the NV component will be set to the same value as the input slot of the BACnet data point, which is connected to NV component.
WARNING! This mechanism works only if the value of the connected slot (priority input) to the NV component will be changed from the BACnet protocol level. If the value of different priority input will be changed from the BACnet protocol level, the action “Link back forward ” will not be executed, and the output value will be chosen from object priority array.