Hart®-Communication - ABB FSM4000 Operating Instructions Manual

8.4
8.4.1
HART
communicate without any added installation expenses. The 4–20 mA current output signal transmits both
the process information and the digital signal used to communicate bidirectionally. The analog process value
output allows connection to analog indicators, recorders and controllers while the simultaneous digital
communication uses HART-Protocol.
The HART-Protocol utilizes Frequency Shift Keyed (FSK) modulation for communication based on the Bell
Standard 202. The digital signal is composed of two frequencies 1200 Hz and 2200 Hz, which represent the
1 or 0 bit information.
This design utilizes the HART hard- and software and the 4–20 mA current output. Terminals 31/32 require
a load of at least 250 Ω.
Fig. 15:
A FSK-Modem must be installed for HART-Communication when connecting to a PC. The HART-Modem
converts the analog 4–20 mA signal into a digital output signal per the Bell 202 Standard with a RS 232C
output to the PC.
The SM4000 can also be configured and accessed using a handheld terminal Type 275. The connection is
made in parallel with the 4–20 mA current output. Please see the Operating Instruction for the Handheld
Terminal for details.
The software program SMART VISION from ABB can be used in the control room or the service area to
monitor and evaluate the data from field instruments utilizing the HART-Protocol. The SMART VISION
program includes the ability to configure and display the process relevant variables with a periodic self
monitoring function to check the connected field instruments.
8.4.2
General Description
SMART VISION
instruments.
SMART VISION
„common practice" HART-Commands. For ABB-instruments, the manufacturer specific commands are also
supported, so that the entire functional range of the instruments can be utilized.
SMART VISION
within the framework of Profile Specification 2.0/3.0.
D184B122U02 S4
®
HART -Communication
®
HART -Protocol
®
-Protocol provides the ability to simultaneously output process variables and to digitally
R min = 250 Ohm
b
PC
Communication with HART-Protocol
Software SMART VISION
®
is a universal and intuitive graphic Management Software for use with intelligent field
®
communicates with all HART-capable instruments within the extent of the „universal" and
®
supports both HART- and PROFIBUS-DTMs as well as all other PROFIBUS instruments
4-20 mA
HART
Bell 202
Modem Box
Handheld Terminal
®
Converter
Qn 50.05 m3/h
Qn 1500 m3
CPU DN Q DN QmaxF Display
1 2 3 4
Low.-F Puls Counter Test
Contrast
5 6 7 8
Tot Damp.
9 0 .
+/- C/CE Enter
Flowmeter Primary
41