The DeltaV system connects to the fieldbus segment through an H1 card. The DeltaV system enables you to graphically configure your fieldbus devices and H1 cards, establish communication between fieldbus and conventional devices, and monitor the performance of the control loops operating in the fieldbus devices. In the DeltaV Explorer, the H1 cards are under the I/O subsystem for the controller associated with the fieldbus device. Each fieldbus card has two ports and each port can connect to one fieldbus segment. fieldbus ports are indicated by the 
icon in the DeltaV Explorer. Up to 16 devices are supported for each segment. The H1 card and the ports associated with the card manage the fieldbus device behaviors.