KROHNE FMCW80G74TA ユーザーズマニュアル

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9
 DESCRIPTION OF HART INTERFACE 
108 
OPTIWAVE 7500 C
www.krohne.com
10/2016 - 4004375401 - MA OPTIWAVE 7500 R01 en
9.3  Connection variants
The signal converter is a 2-wire device with 4...20 mA current output and HART® interface.
• Multi-Drop Mode is supported
Multi-Drop Mode is supported
Multi-Drop Mode is supported
Multi-Drop Mode is supported
In a Multi-Drop communication system, more than 1 device is connected to a common 
transmission cable.
• Burst Mode is not supported
Burst Mode is not supported
Burst Mode is not supported
Burst Mode is not supported
There are two ways of using the HART® communication:
• as Point-to-Point connection and
• as Multi-Drop connection with 2-wire connection.
9.3.1  Point-to-Point connection – analogue / digital mode
Point-to-Point connection between the signal converter and the HART® Master.
The current output of the device is passive.
Also refer to 
Point-to-point connection
 on page 37.
9.3.2  Multi-Drop connection (2-wire connection)
Up to 63 devices may be installed in parallel (this signal converter and other HART® devices).
For an illustration of multi-drop networks, refer to 
Multi-drop networks
 on page 38.
9.4  HART® device variables
The HART® dynamic variables PV (Primary Variable), SV (Secondary Variable), TV (Third Variable) 
and QV (Fourth Variable) can be assigned to any of the device variables.
PDM version:
≥ 6.0
FDT version:
≥ 1.2
HART® device variable
Code
Type
sensor value
0
linear
level
1
linear
distance
2
linear
reflection
3
linear
level linearization
 1
4
linear
volume conversion
 2
5
linear
mass conversion
 2
6
linear
distance linearization
 1
7
linear
ullage volume conversion
 2
8
linear
ullage mass conversion
 2
9
linear
1 This HART® device variable is available if you created a linearization table in the conversion menu
2 This HART® device variable is available if you created a strapping table in the conversion menu