Transducer blocks description, Flow transducer block parameters – Fluid Components International ST100 Series PROFIBUS PA User Manual

Page 11

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ST100 Series Profibus PA

Fluid Components International LLC

7

Transducer Blocks Description
There are 3 Process Data Transducer blocks in the ST100, one for each of the process variables that the ST100 can measure, flow, temperature, and

pressure.

Note:

Not every process variable is available in every ST100 model.

Flow Transducer Block Parameters
There are three possible flow types; but only one is active at a time. The active flow type is the only one that has valid data in that structure of the

block.

REL. INDEX

PARAMETER

SLOT

INDEX

DATA TYPE (LENGTH)

STORE SIZE READ/WRITE

8

CALIBR_FACTOR

6

24

FLOAT

S

4

RW

9

LOW_FLOW_CUTOFF

6

25

FLOAT

S

4

RW

10

MEASUREMENT_MODE

6

26

UNSIGNED 8

S

1

RW

11

FLOW_DIRECTION

6

27

UNSIGNED 8

S

1

RW

12-14

NOT USED

6

28-30

15

NOMINAL_SIZE

6

31

FLOAT

S

4

RW

16

NOMINAL_SIZE_UNITS

6

32

UNSIGNED 16

S

2

RW

17

VOLUME_FLOW

6

33

101(DS-33)

D

5

R

18

VOLUME_FLOW_UNITS

6

34

UNSIGNED 16

S

2

RW

19

VOLUME_FLOW_LO_LIMIT

6

35

FLOAT

S

4

R

20

VOLUME_FLOW_HI_LIMIT

6

36

FLOAT

S

4

R

21

MASS_FLOW

6

37

101(DS-33)

D

5

R

22

MASS_FLOW_UNITS

6

38

UNSIGNED 16

S

2

RW

23

MASS_FLOW_LO_LIMIT

6

39

FLOAT

S

4

R

24

MASS_FLOW_HI_LIMIT

6

40

FLOAT

S

4

R

25-42

NOT USED

6

41-58

43-52

RESERVED BY PI

6

59-68

53

VELOCITY_FLOW

6

69

101(DS-33)

D

5

R

54

VELOCITY_UNITS

6

70

UNSIGNED 16

S

2

RW

55

VELOCITY_LO_LIMIT

6

71

FLOAT

S

4

RW

56

VELOCITY_HI_LIMIT

6

72

FLOAT

S

4

RW

57

DEVICE_VARIABLE_CODE

6

73

UNSIGNED 8

D

1

R

The following parameters are in the block for compatibility with the profile for flow but perform no real function since the method of measurement

used by the ST100 does not use those parameters. The parameters are CALIBR_FACTOR, LOW_FLOW_CUTOFF, MEASUREMENT_MODE, and

FLOW_DIRECTION.
The NOMINAL_SIZE, and the NOMINAL_SIZE_UNITS parameters are used by the Volume flow and the Mass flow. These parameters are associated

with the pipe dimensions and units. NOMINAL_SIZE is the diameter of the pipe.
The DEVICE_VARIABLE_CODE is use to identify the active flow type that the instrument is operating in. The Volume Code = 0, the Mass Flow

code = 3, and the velocity flow code = 4.

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