What are the different HART networks?



In point-to-point mode, the traditional 4–20 mA signal is used to communicate one process variable, while additional process variables, configuration parameters, and other device data are transferred digitally using the HART protocol. The communication takes place between two devices .

Multi drop:-

The multi drop mode of operation requires only a single pair of wires and, if applicable, safety barriers and an auxiliary power supply for up to 15 field devices All process values are transmitted digitally. In multi drop mode, all field device polling addresses are >0, and the current through each device is fixed to a minimum value (typically 4 mA).