Emerson 2400S - Manual (Page 19)

Installation Manual 15
I/O Wiring – Model 2400S Analog Transmitters
P
o
wer Su
ppl
y
I/O
W
irin
g
– DP
an
d
DN
I/
O W
iri
n
g
– AN
Be
fo
re
Y
o
u
Begin
Figure 3-5 Required external voltage versus mA load resistance
Figure 3-6 HART multidrop wiring – Internal or external power
0
4
8
12
16
20
24
28
30
0 200 400 600 800 1000 1200
If communicating with HART, a minimum of 250 Ohms is required.
Total mA load resistance (Ohms)
Mi
nim
u
m req
u
ired
e
x
ter
n
al v
o
lt
a
ge (V
olts)
OPERATING REGION
HART-compatible
host or controller
HART-compatible
transmitter
SMART FAMILY ™
transmitter
Note: For optimum HART communication, make sure the output loop
is single-point-grounded to an instrument-grade ground.
24 VDC loop power
supply required for
HART 4–20 mA
passive transmitters
600 Ohm maximum resistance
250 Ohm minimum resistance
Model 2400S
External power
Model 2400S
Internal power