E-Zine March 2012
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Since addressing devices is performed digitally during configuration, wiring termination is much easier because each wire pair must only be terminated on an interface card, and not necessarily to a specific termination location. This tends to eliminate the time-consuming ringing-out of wires for each field instrument during installation.
FOUNDATION™ Fieldbus H1 instruments may also terminate in a FOUNDATION™ Fieldbus HSE Linking Device that can be located in the field junction box.
Relatively low cost Category 5E Ethernet connecting cable can be run to an industrial-grade Ethernet switch located in the field. The Ethernet switch is then connected to the control system using standard Ethernet wiring, but is often implemented using commercial Ethernet fiber optic cables for the long runs to gain both isolation and distance. The speed and capacity advantages of Ethernet fiber optics often provide a cost advantage as compared to using long multi-pair cables. The use of HSE can usually reduce wiring costs more than is possible with use of H1 alone.
Excerpted from The Consumer Guide to Fieldbus Network Equipment for Process Control