Emerson Rosemount 2410 Reference Manual page 41

Reference Manual
00809-0100-2410, Rev DA
Example 1
The example illustrated in
Hub acting as power supply. In the calculations below it is assumed that the cable length between the
field devices on the tank can be ignored.
The tank is equipped with the following field devices: a Rosemount 5900S Radar Level Gauge, a
Rosemount 2240S Multi-input Temperature Transmitter, and a Rosemount 2230 Graphical Field Display.
The total current consumption of the three devices is 110 mA (see
Figure 3-2. Installation on one tank
Rosemount 2410 Tank Hub
The total operating current of the connected field devices on the tank is 50+30+30 mA=110 mA. This is
within the output capability of the Rosemount 2410 Tank Hub.
Calculations
The tank hub is powered by an intrinsically safe power supply: 12.5 V, 250 mA.
Voltage drop to the tank:
110 mA x 0.30 km x 42 /km=1.4 V.
Voltage at the tank =12.5 V - 1.4 V=11.1 V.
Result: the input voltage of 11.1 V to the field devices is above the minimum requirement of 9 V.
Installation
Figure 3-2
Tankbus
Voltage drop=1.4 V
includes a tank located 300 m away from a Rosemount 2410 Tank
Rosemount 2230 Display
300 m
Installation
Table 3-2 on page 28).
Rosemount 2240S
Temperature Transmitter
Rosemount 5900S
Radar Level Gauge
March 2017
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