ExternalSensor is an optional component from DeviceZoneType and includes variables for the operation with an external temperature sensor. The temperature sensor is connected at the TCD directly or the value can come from the connected machine.
Table 10 – ExternalSensorType Definition
|
Attribute |
Value |
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|
BrowseName |
ExternalSensorType |
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|
IsAbstract |
False |
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|
References |
Node Class |
BrowseName |
DataType |
TypeDefinition |
Other |
|
Subtype of 0:aseObjectType defined in OPC UA Part 5 |
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|
0:HasComponent |
Variable |
ActualValue |
0:Double |
0:AnalogItemType |
M, RW |
|
0:HasProperty |
Variable |
Used |
0:Boolean |
0:PropertyType |
M, RO |
|
0:HasComponent |
Method |
ExternalSensorModeOn |
|
|
M |
|
0:HasComponent |
Method |
ExternalSensorModeOff |
|
|
M |
|
0:HasComponent |
Variable |
ThermocoupleType |
0:UInt16 |
0:MultiStateValueDiscreteType |
M, RW |
|
0:HasComponent |
Variable |
CommunicationProtocolType |
0:UInt16 |
0:MultiStateValueDiscreteType |
M, RW |
|
0: HasProperty |
Variable |
AutomaticModeSwitch |
0:Boolean |
0:PropertyType |
O, RW |
|
0:HasComponent |
Object |
ClosedLoopControl |
|
3:ClosedLoopControlType |
O |
Description:Actual value of external temperature sensor
Unit:°C or °F
Example: 41.0
The value is only writeable if the CommunicationProtocolType is OPC_UA (value 3).
Description:Return whether an external temperature sensor is used for control
Example: true
Description:Activate the mode where the external temperature sensor is used for temperature control
Signature
ExternalSensorModeOn ();
Description:Deactivate the mode where the external temperature sensor is used for temperature control
Signature
ExternalSensorModeOff ();
This two Variables are used to specify the type of connected external temperature sensor and the used communication protocol between the sensor and the control system of the TCD.
The TypeDefinition for both Variables is MultiStateValueDiscreteType, so the Properties EnumValues and ValueAsText must be filled with the supported values out of Table 11 and Table 12.
Table 11 – Values for ThermocoupleType
|
EnumValue |
ValueAsText |
Description |
|
0 |
OTHER |
Other sensor type |
|
1 |
E |
Type E sensor: NiCr-CuNi |
|
2 |
J |
Type J, L sensor: Fe-CuNi |
|
3 |
K |
Type K sensor: NiCr-Ni |
|
4 |
N |
Type N sensor: NiCrSi-NiSi |
|
5 |
T |
Type T sensor: Cu-CuNi |
|
6 |
PT100 |
Pt 100-Sensor |
Table 12 – Values for CommunicationProtocolType
|
EnumValue |
ValueAsText |
Description |
|
0 |
OTHER |
Other connection type |
|
1 |
LOCAL |
Communication integrated in the local control system (local input) |
|
2 |
PROFIBUS |
Values via Profibus |
|
3 |
OPC_UA |
Values via OPC UA |
|
4 |
I2C |
Values via I2C |
|
5 |
CAN |
Values via CAN |
Which sensor types and protocols and combinations are supported is device dependent. Especially when the CommunicationProtocolType has the value 1 (LOCAL), the ThermocoupleType could be set to a fixed value by the TCD.
Setting whether switching to external sensor is performed automatically (TRUE) or manually (FALSE). If TRUE, temperature control is regulated to the external sensor when the external sensor is plugged, and again switched automatically to the internal measurement site when the external sensor is unplugged.
With this Object of ClosedLoopControlType (defined in OPC 40083) the client can do settings for the closed loop control for the sensor.