INFICON BCG450-SP ATM to Ultra-High Vacuum Triple Gauge (Profibus) User Manual

Page 27

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tira41e1 (2005-06) BCG450SPv1.cp

27

Instance 2 of the Analog Sensor Input Function Block describes the functionality of
the BA measuring part of the gauge.

In Instance 2, the same attributes as in Instance 1 are supported:

ID

Name

Structure Data type

Bytes

Access

Store

19

Process Value
(PV)

Simple

According to
Parameter Data
Type

-

0_XI
1_R
2_R

D

20

Status

Simple

Unsigned8

1

0_XI
1/2_R

D

21

Data Type

Simple

Unsigned8

1

2_R/W

N

22

Data Units

Simple

Unsigned16

2

2_R/W

N

23

Reading Valid

Simple

Boolean

1

1_R
2_R

D

24

Full Scale

Simple

According to
Data Type value
(parameter 21)

-

1/2_R

N

39

Safe State

Simple

Unsigned8

1

1/2_R/W

N

40

Safe Value

Simple

According to
Data Type value
(parameter 21)

-

1/2_R/W

N

44

Overrange

Simple

According to
Data Type value
(parameter 21)

-

1/2_R

N

45

Underrange

Simple

According to
Data Type value
(parameter 21)

-

1/2_R

N

The Process Value contains the measured value of the BA Device Instance in the
currently selected data unit (ID 22) and in the selected data type (ID 21).

If the device is not in the EXECUTING status (ID 25, Device Block), the value
defined in the Safe State is output.

Values output in the data unit COUNTS can be converted into a pressure value by
means of the following formulas:

Calculation of the pressure (PV is the abbreviation used for Process Value):

PV

mbar

=

10

(COUNTS / 2000) - 12.5

PV

Torr

=

0.75006168 × PV

mbar

PV

Micron

=

10

-3

× PV

Torr

PV

Pa

=

100 × PV

mbar

This parameter is remains on "0".

Two data types are supported: Float and Integer16.

In cyclic data traffic, the data type cannot be modified. The data type setting can
only be modified when the gauge is in the IDLE status. By defining the configura-
tion data for cyclic data traffic (selection of standard telegram), the data type used
in the selected standard telegram is taken over. All settings previously made in
acyclic data traffic are thus overwritten.

If the data type is set in one instance, that data type setting applies to all instances.
Likewise, when a standard telegram is selected, the data type used by that
standard telegram will be valid for all instances

Coding

Data type

3

Integer16

8

Float

3.2.3

Analog

Sensor

Input Function Block
Instance 2 / SLOT 1

3.2.3.1 Process Value

3.2.3.2 Status

3.2.3.3 Data Type

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