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Introduction

Fieldbus is an all-digital, two way, multi-drop communication system
Implements distributed control
Control by devices
I/P,O/P and process control devices configured
Used for
Process control
Process monitoring

Devices

Devices-field devices or host
device tag
string name
Unique on n/w
configurable attribute
type of device
Address
ID
serial no.
Unique to the device
assigned by manufacturer
not configurable

Types of devices

3 types of devices on H1 n/w
Link master
Controls commn. traffic on a page link by scheduling
An interface board in PC, dcs, valve, pt
FB operate independently of a cp sys.because of linkmasters
Have processing and controlling capability
Link Active Scheduler(LAS)-currently active page link master
Publishes time information
Grants permissions to devices
Basic devices
not capable of scheduling commn.
Cannot become LAS
H1 bridges
Connects links together into a spanning tree

H1 & HSE

2 communication protocols
H1(transmits at 31.25Kb/s connecting field devices)
HSE(High Speed Ethernet uses 10 or 100Mbps Ethernet as the physical layer)
H1 links interconnected by H1 data page link bridges
HSE to H1 interconnections by linking devices

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