Power Supply - Emerson Rosemount 2088 Reference Manual

Reference Manual
00809-0100-4108, Rev BA
4.6.2

Power supply

4-20 mA HART (option code S)
Transmitter operates on 10.5-42.4 Vdc at the terminal of the transmitter. The dc power supply
should provide power with less than two percent ripple. A minimum of 16.6V is required for
loops with a 250  resistance.
Note
A minimum loop resistance of 250 s is required to communicate with a field communicator. If
a single power supply is used to power more than one Rosemount 2088 transmitter, the power
supply used, and circuitry common to the transmitters, should not have more that 20 s of
impedance at 1200 Hz.
Figure 4-5. Load limitation
The field communicator requires a minimum loop resistance of 250
The total resistance load is the sum of the resistance of the signal leads and the load resistance
of the controller, indicator, I.S. Barriers, and related pieces. If intrinsic safety barriers are used,
the resistance and voltage drop must be included.
1-5 Vdc low power HART (output code N)
Low power transmitters operate on 9-28 Vdc. The dc power supply should provide power with
less than 2 percent ripple. The V
Electrical installation
Maximum Loop Resistance = 43.5 * (Power Supply Voltage – 10.5)
1387
1000
500
0
10.5
out
Operating
Region
20 30
42.4
Voltage (Vdc)

for communication.
load should be 100 k or greater.
Section 4: Electrical Installation
March 2014
45