Emerson Rosemount 644h, Reference Manual

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Reference Manual
00809-0100-4728, Rev HA
December 2002
Models 644H and 644R
3-2
MODEL 275 HART
COMMUNICATOR
The HART Communicator exchanges information with the transmitter from
the control room, the instrument site, or any wiring termination point in the
loop. To facilitate communication, connect the HART Communicator in
parallel with the transmitter (see Figure 2-11). Use the loop connection ports
on the rear panel of the HART Communicator. The connections are
non-polarized. Do not make connections to the serial port or the NiCad
recharger jack in explosive atmospheres. Before connecting the HART
communicator in an explosive atmosphere, make sure the instruments in the
loop are installed in accordance with intrinsically safe or non-incendive field
wiring practices.
For more information regarding the Model 275 HART Communicator, please
see the Model 275 HART Communicator Reference Manual (document
number 00809-0100-4275)
CONFIGURATION
The Model 644 transmitter can be configured either on-line or off-line using a
Model 275 HART Communicator or AMS. During on-line configuration, the
transmitter is connected to a HART communicator. Data is entered in the
working register of the communicator and sent directly to the transmitter.
Off-line configuration consists of storing configuration data in a HART
Communicator while it is not connected to a transmitter. Data is stored in
nonvolatile memory and can be downloaded to the transmitter at a later time.