What is the difference between fieldbus and Hart?
Difference Between Fieldbus and HART Communication Protocols HART (Highway Addressable Remote Transducer) and Foundation Fieldbus are both digital communication systems used in process automation. However, they work, are built, and operate quite differently.
HART Communication:
HART was first used in the 1980s and is still frequently used today because it is easy to use and works with older 4–20 mA analog systems. It adds a digital signal (1200 bps) to the 4–20 mA current loop, which lets smart field devices and control systems talk to each other without changing the analog measurement. The analog signal usually stands for the main process variable (PV), while extra digital data gives supplementary parameters and diagnostics. HART works in a master/slave setup, with one main master (like a DCS) and one secondary master (like a portable communicator). Multi-drop arrangements are feasible, although they are slow and not often used. HART is suitable for upgrading brownfields and for applications that need easy monitoring and configuration.
Foundation Fieldbus:
Foundation Fieldbus is a digital, two-way communication network that works at 31.25 kbps. It was first used in the late 1990s. It can power and talk to all of the devices at the same time, unlike HART, which only lets one device on a pair of wires. It allows for control in the field, enhanced diagnostics, time-stamped data, and devices from multiple suppliers to work together. Fieldbus cuts down on wiring, I/O hardware, and commissioning time by a lot, while making the system more reliable and flexible. HART is a hybrid analog-digital protocol that works well with older systems. Foundation Fieldbus, on the other hand, is a pure digital control network that is meant for modern, integrated, and smart process automation.