4 s-analog sensor object, 1 class attributes 4.4.2 semantics, 3 instance attributes – INFICON PSG55x ATM to Medium Vacuum Gauge (DeviceNet) User Manual
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tira58e1-a (2012-03) PxG5xx.cp
Class Code 31
h
= 49
d
Attribute ID Access
rule
Name
DeviceNet
data type
Description of attribute
Semantics of values
1
Get
Revision
UINT
Revision of this object Note: All class definitions are
required to include this class attribute.
The current value
assigned to this attrib-
ute is one (01).
2 Get
Max
instance
UINT
Maximum instance number of an object currently
created in this class level of the device.
The largest Instance
number of a created
object at this class
hierarchy level.
32 Get
Class
Level
Status
Extension
USINT
Bit 0: Reading Invalid
Bit 1: Overrange Exceeded
Bit 2: Underrange Exceeded
94 Get
Active
value
INT or
specified by
data type
Is used by assemblies to produce this class-level
attribute, instead of the value (attribute ID 6) of the
S-Analog sensor instances.
95 Get
Active
instance
number
UINT
Identifies the object instance that is providing the
value which is copied into the active value for all
input assemblies and the alarm/warning exception
details for the S-Device supervisor object.
→ Behavior section.
Default = 1
96 Get
Number
of
gauges
USINT
Identifies the number of gauge instances present in
the device.
PSG55x: 1
PCG55x: 2
99
Get
Subclass
UINT
Identifies a subset of additional class attributes,
services and behaviors.
1
≙
Instance selector
Assemblies or connections may produce this class-level attribute, instead of the
value (attribute ID 6) of the active S-Analog sensor instance. The S-Analog sensor
class-level attribute active instance number identifies the object instance that is
currently active and providing the value to the active value class-level attribute
which is, in turn, produced by the input assemblies that have active value as a
member.
The device internally modifies this attribute, as required, to identify the S-Analog
sensor object instance providing the value member which is copied into the active
value for all input assemblies and the alarm/warning exception details for the
S-Device supervisor object.
→ Behavior for more information on the mechanism.
This attribute is used to determine the size of all input assemblies within a node.
→ respective device profile for its usage within a device type.
Two S-Analog sensor instances (instance 1 and instance 2) are available by
PCG55x.
Instance 1 represents the physical sensor reading of the capacitance diaphragm
gauge.
Instance 2 represents the physical sensor reading of the heat transfer vacuum
gauge.
The PSG550 has only the instance1. In this case instance 1 represents the
physical sensor reading of the heat transfer vacuum gauge.
4.4 S-Analog Sensor Object
4.4.1 Class Attributes
4.4.2 Semantics
Active value
Active instance number
Number of gauges
4.4.3 Instance Attributes