Installation, Operation and Maintenance Manual
MDE 255 Rev. 1 April 2021
Foundation™ Fieldbus Overview 5
Section 5: Foundation™ Fieldbus Overview
Section 5: Foundation™ Fieldbus Overview
Foundation Fieldbus is an open networking standard which provides an open specification for both the
control application and the communication on the bus.
Foundation Fieldbus communication protocol is an industry proven international standard
(IEC 61158-2) designed for use in the process industry and also complies with the ISA-SP50
recommendation for fieldbus devices.
The major benefits in adopting this standard includes:
• Multi-drop capability with up to 32 devices per segment;
• Extended trunk length using repeaters which increase the total bus length and the number
of devices in the network;
• Power and communications over the same shielded twisted pair network that allow to know
the physical status of ICON3000 actuator even if it is without actuator mains power;
• Distribution of the control into the field devices reducing the amount of control equipment
in the plant.
This last item is one of the more advantages of Foundation Fieldbus which uses standards ‘Function
Blocks’ and Device Descriptions to implement control strategy. Function Blocks are standardized
automation functions with defined behaviour used to represent different type of functions such
as discrete input (DI), discrete output (DO), analog input (AI), analog output (AO), Proportional /
Integral / Derivative (PID), etc.
Furthermore, every Foundation Fieldbus device has a Resource Block and at least a Transducer Block.
Once the hardware of a Foundation Fieldbus device is configured, fieldbus communication is used to
configure the transducer block parameters. The desired transducer functionality is associated with a
specific function block via a Channel.
The host system is used to link the function blocks together to create a control application that can
be downloaded to the devices in the segment.
More information about Foundation Fieldbus are in the documents:
• Foundation Fieldbus – Technical Overview
• Foundation Fieldbus – Wiring and installation 31.25 kbit/second, Voltage Mode,
Wire Medium Application Guide
Available at the website http://www.fieldbus.org
