5. What Is Fieldbus? P L F Automation and Display Systems Fieldbus Process Plant Fieldbus - a digital, two-way multi-drop communication link among intelligent measurement and control devices, and automation and display systems.
6.
7.
8. F OUNDATION Fieldbus Benefits REDUCED WIRING AND INSTALLATION Traditional 4-20 mA wiring, one IS barrier, one pair for each device 4-20 mA IS IS IS IS One IS barrier, one pair for many devices IS Fieldbus
9. F OUNDATION Fieldbus Benefits EXPANDED VIEW OF PROCESS IS IS IS IS 4-20 mA Fieldbus IS
10.
11. F OUNDATION Fieldbus Benefits DISTRIBUTION OF FUNCTIONS PID PID 4-20 mA PID AO AI In today’s systems, control functions all reside in central controllers. Fieldbus can be used in the same way, but fieldbus also enables control and I/O functions to be distributed to field instruments. AI IS Fieldbus AO
12.
13.
14. Fieldbus Wiring 24v Nom Fieldbus Power Supply Terminator Terminator Fieldbus Wire Signal Isolation Circuit Fieldbus Devices
17. Shielded Twisted Pair Cable Cable Jacket Shield Drain Wire Two Colors of Power/Signal Wire Shield with 90% Coverage
18. Terminal Blocks To Control Building (Single or Multi-Pair) (Shielded) Inside Junction Box Field Devices Twisted Pair (Shielded) Shields not shown Fieldbus Terminator
19.
20.
21.
22.
23. Wiring Two Devices on a Segment Power supply not shown = Terminators, in J-Box Spurs with one device are limited to 120 meters each J-Box J-Box Single or multi-pair cable Spur T T T
24.
25.
26. Wiring Using Tree Topology T T Homerun Cable 120 Meter Spur HMI J-Box This fieldbus includes 4 devices and 3 devices on three spurs, so maximum spur length is 120 meters (next table) Power supply not shown = Terminators T
27. Maximum Spur Lengths Total Devices On Segment 1 Device per Spur 2 Devices per Spur 3 Devices per Spur 4 Devices per Spur 25 - 32 1 m 1 m 1 m 1 m 19 - 24 30 m 1 m 1 m 1 m 15 - 18 60 m 30 m 1 m 1 m 13 - 14 90 m 60 m 30 m 1 m 2 - 12 120 m 90 m 60 m 1 m Recommended Maximum Spur Length
28. Cable Types / Bus Segment Length Cable Type Gauge No. Max. Length A: Twisted-pair with Shield H1 (31.25kbps) #18AWG 1900 m B: Multi-twisted-pair with Shield H1 (31.25kps) #22AWG 1200 m C: Twisted-pair without Shield H1 (31.25kbps) #22AWG 400 m D: Multi-core with Shield H1 (31.25kbps) #16AWG 200 m Any existing, good quality #18 AWG twisted pair cable can be used for fieldbus.
29. Cable Length Calculation Cable Type A B C D H1 Total Length* 1900 m / 6234 ft 1200 m / 3937 ft 400 m / 1312 ft 200 m / 656 ft * Total length including all spurs Terminators and power supplies not shown Field Devices J Box Spur Homerun Cable # of Devices 25 - 32 19 - 24 15 - 18 13 - 14 2 - 12 Total Max Spur Length** 1 m / 3 ft 30 m / 98 ft 60 m / 197 ft 90 m / 295 ft 120 m / 394 ft ** Maximum length of any spur
30. Exceeds Maximum Spur Length T 500 m 500 m Homerun cable T J Box J Box J Box No Good
31. Correct Installation J Box J Box J Box T 500 m 500 m Homerun cable T Fieldbus Repeater T T
32. More Control with Installed Wires J-Box Three existing 4-20 mA Pairs T T Fieldbus devices Three existing pairs, one used for fieldbus J-Box
![[object Object],[object Object],[object Object]](https://image.slidesharecdn.com/ffpresentation-12767568634225-phpapp01/85/FF-Presentation-1-320.jpg)
![Purpose of this Presentation ,[object Object],[object Object],[object Object],[object Object]](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)