Emerson 3051N User Manual

Page of 100
Reference Manual
00809-0100-4808, Rev CA
June 2008
A-5
Rosemount 3051N
CONNECTIONS AND 
HARDWARE
The HART Communicator can interface with a transmitter from the control 
room, the instrument site, or any wiring termination point in the loop through 
the communicator connections as shown in Figure A-2 and Figure A-3. T
communicate, connect the HART Communicator in parallel with the 
instrument or load resistor. The connections are non-polarized. Before 
connecting the HART Communicator in an explosive atmosphere, make sure 
the instruments in the loop are installed in accordance with intrinsically safe or 
nonincendive field wiring practices.
NOTE
The HART Communicator needs a minimum of 250 ohms resistance in the 
loop to function properly. The HART Communicator is not a measurement 
device and does not need to be calibrated; it is a communications device 
through which you can read and adjust the transmitter configuration 
information. All variable outputs displayed by the communicator are functions 
of the transmitter.
FIGURE A-2. Rosemount 275 
Rear Connection Panel with 
Optional NiCad Recharger 
Pack.
NOTE
Do not make connections to the serial port or NiCad recharger jack in an 
explosive atmosphere.
FIGURE A-3. Rosemount 375 
HART terminal access door.
Loop Connection Ports
Serial Port
NiCad
recharger
jack
HART Terminal Markings
IrDA interface 
(for PC communication)