Spirax Sarco RIM20, Инструкция по установке и обслуживанию, Страница: 70 / 132

IM-P198-05 MI Issue 2 70
5. Serial communications
5.1 HART communications
The HART Communications Protocol (Highway Addressable Remote Transducer Protocol) is
a bidirectional digital serial communications protocol. The HART signal is based on the Bell
202 standard and is superimposed on 4-20 mA Output 1. Peer-to-peer (Analogue / digital)
and multi-drop (digital only) modes are supported.
Warning!
Place controls in manual mode when making configuration changes to the
turbine meter.
5.2 Wiring
The diagrams below detail the proper connections required for HART communications:
5.2.1 Loop powered meter wiring
Fig. 48 Loop Powered Meter Wiring (HART)
LO
O
P
P
O
W
E
R
+
-
F
R
E
Q
O
U
T
P
U
LS
E
O
U
T -
-
+
+
O
P
T
IO
N
A
L
B
A
C
K
LI
G
H
T
P
O
W
E
R
+
-
R load,
250 ohm
minimum
+
_
d c
Power
Supply
Remote Connection
for Communicator
Current
Meter
Field Connection
for Communicator
Turbine Meter
Current
meter
Turbine
meter
R load,
250 ohm
minimum
dc
power
supply
Field connection for
communicator
Remote
connection for
communicator