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MAN-100472
RD150 - Operating Instructions
57030-EN-180717
Connection of the feeding power supply
unit
Networks of overvoltage category III
Altitude above sea level
Ʋ
by default
up to 2000 m (6562 ft)
Ʋ
with connected overvoltage protection up to 5000 m (16404 ft)
Pollution degree
2)
4
Protection class
II
10.2 HART communication
The HART protocol operates with frequency shift keying (FSK) based on the data communication
standard Bell 202. The digital signal is generated from the frequencies 1200 and 2200 Hz, which
represent the bit information 1 and 0. Sine curves with these frequencies are superimposed on the
direct current in the wire pair of the field instrument. The average value of the superimposed signal
is zero. For that reason, the 4 … 20 mA signal is not influenced by the simultaneous digital data
transmission.
Supported HART commands
Command no.
Command name
Description
0
Read Unique Identifier
Sensor identification
1
Read primary variable
Primary Value with unit
3
Read current 4 Variables
PV, SV, QV, TV with unit
13
Read Tag, descriptor, date Sensor TAG, …
15
Read output information
Scaling values
18
Write Damping value
Damping
34
Write Tag, descriptor, date Sensor TAG, …
35
Write range values
Write scaling values
36
Set upper range value
Max. adjustment/SPAN
37
Set lower range value
Min. adjustment/ZERO
44
Write PV units
PV unit
2)
When used with fulfilled housing protection
