7
2.0
Standard Function Blocks
2.1
Overview
The function of a F
OUNDATION
fieldbus
™
device is deter-
mined by the arrangement of a system of blocks defined by
the Fieldbus foundation. The types of blocks used in a typi-
cal User Application are described as either Standard or
Advanced.
Function Blocks are built into the F
OUNDATION
fieldbus
™
devices as needed to provide the desired control system
behavior. The input and output parameters of function
blocks can be linked over the Fieldbus and there can be
numerous function blocks in a single User Application.
The Enhanced ECLIPSE Model 706FF is a Guided Wave
Radar (GWR) level transmitter with the following standard
F
OUNDATION
fieldbus
™
Function Blocks:
• One (1) Resource Block (RB)
• Three (3) Custom Transducer Blocks (TB)
• Eight (8) Analog Input Function Blocks (AI)
• Two (2) PID Blocks (PID)
With Advanced Function Blocks:
• One (1) Integrator Block (IT)
• One (1) Arithmetic Block (AR)
• One (1) Input Selector Block (IS)
• One (1) Signal Characterizer Block (SC)
The idea of Function Blocks, which a user can customize
for a particular application, is a key concept of Fieldbus
topology. Function Blocks consist of an algorithm, inputs
and outputs, and a user-defined name.
The Transducer Block (TB) output is available to the net-
work through the Analog Input (AI) blocks. Refer to
Section 2.3 for additional information on the Transducer
Blocks.
The AI blocks take the TB values and make them available
as an analog value to other function blocks. The AI blocks
have scaling conversion, filtering, and alarm functions.
Refer to Section 2.4 for additional information on the
Analog Input Blocks.
As shown in the diagram at left, the End User needs the
Process Variable value as an Analog Input to their fieldbus
network.
BE57-646 ECLIPSE Guided Wave Radar Transmitter - F
OUNDATION
fieldbus
™
Model 706 PVs
TB1 – Level
TB2 – Volume
TB3 – Flow & Totalizers
1
2
3
4
5
6
PV Status
Distance
PV Status
Interface Level
PV Status
Upper Thickness
PV Status
Echo Strength
PV Status
Ifc Echo strength
PV Status
Electronics Temp.
PV Status
Probe Buildup
PV Status
Volume
PV Status
Flow
PV Status
Level
7
8
9
10
PV Status
Head
11
PV Status
NR Totalizer
12
PV Status
R Totalizer
13
Diagnostic Indicators
Diagnostic Indicators
Diagnostic Indicators
NE 107
CF
Process
Data
NE 107
Failure
NE 107
MR
NE 107
Spec
Diagram
Mapping
RB
AI 1
AI 2
AI 3
Integrator
PID 1
AI 4
AI 5
AI 6
AI 7
AI 8
Note: Number next to PV refers to
channel number in the AI Blocks.
Model 706 – transducer Block
