GE FVP110, Руководство по обслуживанию

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System Configuration
About Fieldbus
System Configuration
The following instruments are required for use with Fieldbus devices:
Power supply Fieldbus requires a dedicated power supply. It is recommended
that current capacity be well over the total value of the maxi-
mum current consumed by all devices (including the host). Con-
ventional DC current cannot be used as is.
Terminator Fieldbus requires two terminators. Refer to the supplier for
details of terminators that are attached to the host.
Field devices Connect the field devices necessary for instrumentation.
FVP110 has passed the interoperability test conducted by The
Fieldbus Foundation. In order to properly start Fieldbus, use the
devices to satisfy the requirements of the above test.
Host Used for accessing field devices. A dedicated host (such as
DCS) is used for an instrumentation line while dedicated com-
munication tools are used for experimental purposes.
Cable Used for connecting devices. Refer to
Fieldbus Technical Infor-
mation
(TI 38K3A01-01E) for details of instrumentation cabling.
Provide a cable sufficiently long to connect all devices. For field
branch cabling, use terminal boards or a connection box, as
required. If the total length of the cable is in a range of 2 to 3
meters for laboratory or other experimental use, use a twisted
pair wire with a cross section of 0.9 mm
2
or more (AWG #18)
and cycle period of within 5 cm (2").
Termination processing depends on the type of device being
deployed. For FVP110, use an M4 screw terminal claw. Some
hosts require a connector.
Refer to GE Masoneilan when making arrangements to purchase the recommended
equipment.
The number of devices that can be connected to a single bus and the cable length vary
depending on system design.
When constructing systems, both the basic and overall design must be carefully
considered to allow device performance to be fully exhibited.