Emerson 8800A, Product Manual

Page: 138 / 160

Rosemount Model 8800C Vortex Flowmeter
C-6
CONNECTIONS
AND HARDWARE
The HART Communicator exchanges information with the transmitter
from the control room, the instrument site, or any wiring termination
point in the loop. The HART Communicator should be connected in
parallel with the transmitter.
Figure C-3. Connecting the HART Communicator to a Transmitter Loop
NOTE
The HART Communicator needs a minimum of 250 ohms resistance in
the loop to function properly. The HART Communicator does not
measure loop current directly.
Explosions can result in death or serious injury. 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.
–
–
+
+
Test
Ammeter
R
L
˜
250
W
+
–
–
Power
Supply
Housing Ground
+
+
Communicator
A HART-based communicator may
be connected at any termination
point in the signal loop. Signal loop
must have 250 ohms minimum load
for communications.
–