Emerson Rosemount 2051 Reference Manual page 35

Reference Manual
00809-0100-4107
Figure 2-18: Typical Multidrop Network (4–20 mA only)
A. HART modem
B. Power supply
The product is set to address zero (0) at the factory, which allows operation in the
standard point-to-point manner with a 4–20 mA (1–5 Vdc) output signal. To activate
multidrop communication, the transmitter address must be changed to a number from 1
to 15 for HART Revision 5, or 1–63 for HART Revision 7. This change deactivates the 4–
20 mA (1–5 Vdc) analog output, sending it to 4 mA (1 Vdc). It also disables the failure
mode alarm signal, which is controlled by the upscale/downscale switch position. Failure
signals in multidropped transmitters are communicated through HART messages.
2.11.1 Changing a transmitter address
To activate multidrop communication, the transmitter poll address must be assigned a
number from 1 to 15 for HART
transmitter in a multidropped loop must have a unique poll address.
Changing transmitter address using a Field Communicator
From the HOME screen, enter the Fast Key sequence.
Device Dashboard Fast Keys
Changing transmitter address using AMS Device Manager
Procedure
1. Right select on the device and select Configure.
2. In HART Revision 5 mode:
3. In HART Revision 7 mode:
Reference Manual
®
Revision 5, and 1–63 for HART Revision 7. Each
a) Select Manual Setup, select the HART tab.
b) In the Communication Settings box enter polling address in the Polling
Address box, select Send.
September 2020
HART Revision 5 HART Revision 7
2, 2, 5, 2, 1 2, 2, 5, 2, 2
Configuration
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