Emerson Rosemount 2230, Справочное руководство

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25
Reference Manual
00809-0100-2230, Rev CA
Installation
July 2017
Installation
3.4.5 Power requirements
The Rosemount 2230 is powered over the intrinsically safe Tankbus by the Rosemount 2410 Tank Hub.
The 2410 feeds the intrinsically safe fieldbus segment by acting as a FISCO power supply on the Tankbus
(9 - 17.5 Vdc, polarity insensitive). The Rosemount 2230 has a current consumption of 30 mA.
See the Rosemount 2410 Reference Manual (Document no. 00809-0100-2410) for more information.
When installed in a F
OUNDATION
fieldbus system, the Rosemount 2230 is powered by the FF segment with
standard fieldbus power supplies.
3.4.6 The Tankbus
The Rosemount Tank Gauging system is easy to install and wire. Devices can be “daisy-chained” thus
reducing the number of segment couplers.
In a Rosemount Tank Gauging system devices communicate with a Rosemount 2410 Tank Hub via the
intrinsically safe Tankbus. The Tankbus complies with the FISCO
(1)
F
OUNDATION
fieldbus standard and the
Rosemount 2410 acts as power supply to the field devices on the Tankbus.
Termination
A terminator is needed at each end of a F
OUNDATION
fieldbus network. Generally, one terminator is placed
in the fieldbus power supply, and the other one in the last device in the fieldbus network.
Note
Ensure that there are two terminators on the fieldbus.
The Rosemount 2410 Tank Hub acts as power supply. Since the 2410 normally is the first device in the
fieldbus segment, the built-in termination is enabled at factory.
Other devices such as the Rosemount 5900S Radar Level Gauge, the Rosemount 2230 Graphical Field
Display, and the Rosemount 2240S Multi-input Temperature Transmitter also have built-in terminators
which can easily be enabled by inserting a jumper in the terminal block when necessary.
Segment design
When designing a FISCO fieldbus segment a few requirements need to be considered. Cabling has to
comply with FISCO requirements as described in
“Cable selection” on page 24 .
You will also have to ensure that the total operating current of the connected field devices is within the
output capability of the Rosemount 2410 Tank Hub. The tank hub is able to deliver 250 mA. In a wireless
system the maximum current is 200 mA. Consequently, the number of field devices has to be considered
so that the total current consumption is less than the available current. See section “Power Budget” in
the Rosemount 2410 Reference Manual (Document no. 00809-0100-2410) for more information.
Ensure that all field devices have at least 9 V input voltage at their terminals. Therefore you will have to
take into account the voltage drop in the fieldbus cables.
Distances are normally quite short between the Rosemount 2410 Tank Hub and field devices on the
tank. In many cases you can use existing cables as long as the FISCO requirements are fulfilled (see
“Cable
selection” on page 24 ).
See section The Tankbus in the Rosemount 2410 Reference Manual (Document no. 00809-0100-2410) for
more information on segment design of a Rosemount Tank Gauging system.
1, FISCO=Fieldbus Intrinsically Safe Concept