Siemens SIMATIC ET 200iSP

HART signal
The 󹪝gure below shows the analog signal with the modulated HART signal (FSK method), which
consists of sine waves of 1200 Hz and 2200 Hz and has a mean value of 0. It can be 󹪝ltered out
using an input 󹪝lter so that the original analog signal is available again.
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N"
`N"
C
B
C
B
C
B
C
B
N"
N"
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
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① Analog signal
② Time in seconds
a Command
b Response
Figure 14-8 The HART signal
HART commands and parameters
With SIMATIC PDM you can set the parameters of the HART 󹪝eld devices via HART commands
and read them out via HART responses. The HART commands and their parameters are divided
into three groups with the following properties:
• Universal
• Common practice
• Device-speci󹪝c
Universal commands must be supported by all manufacturers of HART 󹪝eld devices and common
practice commands should be supported. There are also device-speci󹪝c commands that apply
only to the particular 󹪝eld device.
Analog electronic modules
14.10 Basics of HART
ET 200iSP
Operating Instructions, 11/2022, A5E00247483-AK 391