Emerson Rosemount 2230 Water Heater User Manual


 
Reference Manual
300560EN, Rev AA
May 2011
Rosemount 2230
3-8
Section 3. Installation
3.3.6 The Tankbus The Raptor system is easy to install and wire. Devices can be “daisy-chained”
thus reducing the number of segment couplers.
In a Raptor 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. 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.
In a Raptor system 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 Raptor 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 for the Tankbus” on page 3-7.
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 2410 is able to deliver 250 mA. Consequently, the number of field devices
has to be considered so that the total current consumption is less than
250 mA.
Another requirement is to 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 for the
Tankbus” on page 3-7).
See ”The Tankbus” in the Rosemount 2410 Reference Manual (Document no.
305030EN) for more information on segment design of a Raptor system.
(1) FISCO=Fieldbus Intrinsically Safe Concept