INFICON BCG450-SP ATM to Ultra-High Vacuum Triple Gauge (Profibus) User Manual
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tira41e1 (2005-06) BCG450SPv1.cp
Instance 3 of the Analog Sensor Input Function Block describes the functionality of
the Capacitance diaphragm sensor measuring part of the gauge.
In Instance 3, 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 Capacitance diaphragm
sensor Device Instance in the currently selected data unit (ID 22) and in the se-
lected 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.
3.2.4 Analog Sensor Input
Function Block
Instance 3 / SLOT 1
3.2.4.1 Process Value
3.2.4.2 Status
3.2.4.3 Data Type