PROFIBUS is the abbreviation of Process Field Bus, 1989 by Siemens-led 13 companies and 5 research institutions in the standardization norms established in a joint development project. 1996 PROFIBUS as Germany national standard DIN19245, is also a European standard EN50170. PROFIBUS achievement in practical applications, in many bus top, widely used in a variety of industries, is one of the most competitive field bus.
Current PROFIBUS 3 series: PROFIBUS-FMS and PROFIBUS-DP, and PROFIBUS-PA. PROFIBUS-DP has a maximum transmission rate of 12Mbps, applied to the field level, fast, cheap form of transport suitable for automatic control system with real-time communications between field devices. PROFIBUS-FMS workshop level, that is, lower required object-oriented, provide a large amount of data communication services, it has a tendency to be replaced by Ethernet. PROFIBUS-PA specifically designed for process automation, it uses IEC1157-2 technology can be used in potentially explosive environments. PROFIBUS-DP and PROFIBUS-FMS use the same transmission technology and bus access protocol, they can operate on the same cable, and PROFIBUS-PA device via segment Coupler can also be easily integrated into the PROFIBUS-DP network.
PROFIBUS has 3 kinds of transport types: PROFIBUS-DP and PROFIBUS-FMS RS-485 (H2), PROFIBUS-PA IEC1157-2 (H1), fiber optic (FO).
PROFIBUS reference model follows the ISO/OSI model, like FF, it also omits (3~6), adds a user layer. PROFIBUS-DP 1th, 2nd layer and user interface. PROFIBUS-FMS 1, 2, and 7 are defined PROFIBUS-PA data transmission using PROFIBUS-DP Protocol, just upper describes the PA field device behavior rules. Its bus access ways: master station communication between token ring, between the master and the slave master/slave mode. PROFIBUS bus type, tree, Star network topology, you can hook up on the bus 127 sites. PROFIBUS rules developed for the following PROFIBUS protocols laid the Foundation for interoperability between devices. Through the process of equipment specified in accordance with regulations of PROFIBUS parameters, parameters, manufacturer–specific parameters, you can achieve interoperability between devices.