It is assumed that basic concepts of OPC UA information modelling are understood in this document. This document will use these concepts to describe the Machine Tools Information Model. For the purposes of this document, the terms and definitions given in OPC 10000-1, OPC 10000-3, OPC 10000-4, OPC 10000-5, OPC 10000-7, OPC 10000-9, OPC 10000-20 OPC 10000-100, OPC 10000-200, OPC 10031-4, OPC 40001-1, OPC 40001-3 as well as the following apply.

Note that OPC UA terms and terms defined in this document are italicised in the document.

defined message indicating noteworthy information for the operator and for historic dataAn alert can have three subcategories: Error - indicating a state that blocks operation of the process.Warning - indicating a state that requires attention, it can prevent operation in indicated way, however it is generally not blocking operation of the process.Message - display of information the machine tool builder deemed necessary to display, neither blocking or reducing operational capability.

runtime component of the CNC which executes an NC programThis execution may happen in Block Sequence mode (execution of the next NC command starts as soon as the previous has completed), or Single Block Mode (NC channels stops and waits for a NC Start signal to resume executing the next NC program block). A channel contains an assigned set of axes which can be moved in a synchronised interpolated manner. Auxiliary axes may also be assigned to a channel which will usually be commanded in a synchronized uninterpolated manner. An active NC channel runs current NC programs which relate to the workpiece etc. Depending on the machine there may be several active NC channels running simultaneously.

hybrid hardware/software systems that are used for controlling machines

EXAMPLE: Distributed control systems (DCS), programmable logic controllers (PLC), numerical controller (NC), and supervisory control and data acquisition (SCADA) systems.

[SOURCE: ISO 16100-1:2009, 3.7]

mechanical device which is fixed (i.e., not mobile) and powered (typically by electricity and compressed air), typically used to process workpieces by selective removal/addition of material or mechanical deformation

[SOURCE: ISO 14955-1:2017, 3.16, modified: Note to entry deleted]

manual action of inserting a tool into the machine as opposed to an Automatic Tool ChangeThere are two common reasons this is done or necessary: 1) tool life of one group of tools has expired and machining cannot continue until a new tool with sufficient tool life for the next operation is inserted (causing a tool change) 2) a tool for a given job is not available (or defined as "hand tool" meaning it needs to be inserted/changed manually at the time it is needed) and shall be provisioned.

unit of different tools, usually used in order to have several tools available in-process without requiring explicit tool-changesTypical applications are in turning, when one indexed position of the tool revolver holds several outer-diameter cutting inserts and boring tools, such that a tool change process can quickly complete by merely readjusting the CNC setpoint position for the tool compensation.

workpiece of the machine which is worked on with the machine’s technologyThis may be for the purpose of machining, measuring or others, depending on the machine type.

list of all job elements a specific machine knows aboutEXAMPLE: All jobs which were transferred to the machine in some way.

also: production job; concrete implementation of one or more programs or recipes by means of a given orderprovides one to many production programs and the instruction to produce one to many parts; offers the possibility to aggregate the manufacturing of multiple parts or the manufacturing of a part through multiple programs

also: production program; list of operations that the controller performs in sequence;usually a machine-readable file, such as an NC program, which is needed for the controller to fulfil the job; NC programs may also carry a hierarchy of further sub-(NC)programs

tool with equivalent (identical) process capabilities (size and functionality) to an existing tool; used by the controller if the designated tool is locked due to wear, done automatically and/or after user interaction

visual machine state indicator; consists of one or more lamps stacked on top of one another, each having a specific, in most cases different colourThe combination of on/off/blinking lights in the stacklight corresponds to a machine state. The ordering of the colours is counted from the base of the stacklight unit.

exchangeable component used in a machine tool to execute the machining processEXAMPLE: May be drills, ball milling heads, cutting inserts, pinching tools and so forth, or even a non-contact tool like a processing laser.

umbrella term for all media (pressurized air, coolant, lubrication, etc.) and consumables (filters, space in chip carts, etc.) necessary for running the machine.Tools as consumables are excluded from this definition as tools are in their own class of complexity and therefore defined separately.

CNCComputerized Numerical Control

EDMElectrical Discharge Machining

ERPEnterprise Resource Planning

HMIHuman Machine Interface

KPIKey Performance Indicator

MESManufacturing Execution System

MOMode of Operation

NCNumerical Control

OEEOverall Equipment Effectiveness

SCADASupervisory Control and Data Acquisition

VDWVerein Deutscher Werkzeugmaschinenfabriken e.V. (German Machine Tool Builders’ Association)

Node definitions are specified using tables (see Table 2).

Attributes are defined by providing the Attribute name and a value, or a description of the value.

References are defined by providing the ReferenceType name, the BrowseName of the TargetNode and its NodeClass.

• If the TargetNode is a component of the Node being defined in the table the Attributes of the composed Node are defined in the same row of the table.
• The DataType is only specified for Variables; “[<number>]” indicates a single-dimensional array, for multi-dimensional arrays the expression is repeated for each dimension (e.g., [2][3] for a two-dimensional array). For all arrays the ArrayDimensions is set as identified by <number> values. If no <number> is set, the corresponding dimension is set to 0, indicating an unknown size. If no number is provided at all the ArrayDimensions can be omitted. If no brackets are provided, it identifies a scalar DataType and the ValueRank is set to the corresponding value (see OPC 10000-3). In addition, ArrayDimensions is set to null or is omitted. If it can be Any or ScalarOrOneDimension, the value is put into “{<value>}”, so either “{Any}” or “{ScalarOrOneDimension}” and the ValueRank is set to the corresponding value (see OPC 10000-3) and the ArrayDimensions is set to null or is omitted. Examples are given in Table 1.

Table 1 – Examples of DataTypes

Notation	DataType	ValueRank	ArrayDimensions	Description
0:Int32	0:Int32	-1	omitted or null	A scalar Int32.
0:Int32[]	0:Int32	1	omitted or {0}	Single-dimensional array of Int32 with an unknown size.
0:Int32[][]	0:Int32	2	omitted or {0,0}	Two-dimensional array of Int32 with unknown sizes for both dimensions.
0:Int32[3][]	0:Int32	2	{3,0}	Two-dimensional array of Int32 with a size of 3 for the first dimension and an unknown size for the second dimension.
0:Int32[5][3]	0:Int32	2	{5,3}	Two-dimensional array of Int32 with a size of 5 for the first dimension and a size of 3 for the second dimension.
0:Int32{Any}	0:Int32	-2	omitted or null	An Int32 where it is unknown if it is scalar or array with any number of dimensions.
0:Int32{ScalarOrOneDimension}	0:Int32	-3	omitted or null	An Int32 where it is either a single-dimensional array or a scalar.

• The TypeDefinition is specified for Objects and Variables.
• The TypeDefinition column specifies a symbolic name for a NodeId, i.e. the specified Node points with a HasTypeDefinition Reference to the corresponding Node.
• The ModellingRule of the referenced component is provided by specifying the symbolic name of the rule in the ModellingRule column. In the AddressSpace, the Node shall use a HasModellingRule Reference to point to the corresponding ModellingRule Object.

If the NodeId of a DataType is provided, the symbolic name of the Node representing the DataType shall be used.

Note that if a symbolic name of a different namespace is used, it is prefixed by the NamespaceIndex (see 3.4.2.2).

Nodes of all other NodeClasses cannot be defined in the same table; therefore, only the used ReferenceType, their NodeClass and their BrowseName are specified. A reference to another part of this document points to their definition.

Table 2 illustrates the table. If no components are provided, the DataType, TypeDefinition and Other columns may be omitted and only a Comment column is introduced to point to the Node definition.

Table 2 – Type Definition Table

Attribute	Value
Attribute name	Attribute value. If it is an optional Attribute that is not set “--” is used.
References	NodeClass	BrowseName	DataType	TypeDefinition	Other
ReferenceType name	NodeClass of the TargetNode.	BrowseName of the target Node. If the Reference is to be instantiated by the server, then the value of the target Node’s BrowseName is “--”.	DataType of the referenced Node, only applicable for Variables.	TypeDefinition of the referenced Node, only applicable for Variables and Objects.	Additional characteristics of the TargetNode such as the ModellingRule or AccessLevel.
NOTE Notes referencing footnotes of the table content.

Components of Nodes can be complex that is containing components by themselves. The TypeDefinition, NodeClass and DataType can be derived from the type definitions, and the symbolic name can be created as defined in 3.4.3.1. Therefore, those containing components are not explicitly specified; they are implicitly specified by the type definitions.

The Other column defines additional characteristics of the Node. Examples of characteristics that can appear in this column are show in Table 3.

Table 3 – Examples of Other Characteristics

Name	Short Name	Description
0:Mandatory	M	The Node has the Mandatory ModellingRule.
0:Optional	O	The Node has the Optional ModellingRule.
0:MandatoryPlaceholder	MP	The Node has the MandatoryPlaceholder ModellingRule.
0:OptionalPlaceholder	OP	The Node has the OptionalPlaceholder ModellingRule.
ReadOnly	RO	The Node AccessLevel has the CurrentRead bit set but not the CurrentWrite bit.
ReadWrite	RW	The Node AccessLevel has the CurrentRead and CurrentWrite bits set.
WriteOnly	WO	The Node AccessLevel has the CurrentWrite bit set but not the CurrentRead bit.

If multiple characteristics are defined they are separated by commas. The name or the short name may be used.

The NodeIds of all Nodes described in this standard are only symbolic names. Annex A defines the actual NodeIds.

The symbolic name of each Node defined in this document is its BrowseName, or, when it is part of another Node, the BrowseName of the other Node, a “.”, and the BrowseName of itself. In this case “part of” means that the whole has a HasProperty or HasComponent Reference to its part. Since all Nodes not being part of another Node have a unique name in this document, the symbolic name is unique.

The NamespaceUri for all NodeIds defined in this document is defined in Annex A. The NamespaceIndex for this NamespaceUri is vendor-specific and depends on the position of the NamespaceUri in the server namespace table.

Note that this document not only defines concrete Nodes, but also requires that some Nodes shall be generated, for example one for each Session running on the Server. The NodeIds of those Nodes are Server-specific, including the namespace. But the NamespaceIndex of those Nodes cannot be the NamespaceIndex used for the Nodes defined in this document, because they are not defined by this document but generated by the Server.

The text part of the BrowseNames for all Nodes defined in this document is specified in the tables defining the Nodes. The NamespaceUri for all BrowseNames defined in this document is defined in Annex A.

If the BrowseName is not defined by this document, a namespace index prefix like ‘0:EngineeringUnits’ or ‘2:DeviceRevision’ is added to the BrowseName. This is typically necessary if a Property of another specification is overwritten or used in the OPC UA types defined in this document. Table 136 provides a list of namespaces and their indexes as used in this document.

The Attributes of Nodes, their DataTypes and descriptions are defined in OPC 10000-3. Attributes not marked as optional are mandatory and shall be provided by a Server. The following tables define if the Attribute value is defined by this document or if it is server-specific.

For all Nodes specified in this document, the Attributes named in Table 4 shall be set as specified in the table.

Table 4 – Common Node Attributes

Attribute	Value
DisplayName	The DisplayName is a LocalizedText. Each server shall provide the DisplayName identical to the BrowseName of the Node for the LocaleId “en”. Whether the server provides translated names for other LocaleIds are server-specific.
Description	Optionally a server-specific description is provided.
NodeClass	Shall reflect the NodeClass of the Node.
NodeId	The NodeId is described by BrowseNames as defined in 3.4.2.1.
WriteMask	Optionally the WriteMask Attribute can be provided. If the WriteMask Attribute is provided, it shall set all non-server-specific Attributes to not writable. For example, the Description Attribute may be set to writable since a Server may provide a server-specific description for the Node. The NodeId shall not be writable, because it is defined for each Node in this document.
UserWriteMask	Optionally the UserWriteMask Attribute can be provided. The same rules as for the WriteMask Attribute apply.
RolePermissions	Optionally server-specific role permissions can be provided.
UserRolePermissions	Optionally the role permissions of the current Session can be provided. The value is server-specific and depends on the RolePermissions Attribute (if provided) and the current Session.
AccessRestrictions	Optionally server-specific access restrictions can be provided.

For all Objects specified in this document, the Attributes named in Table 5 shall be set as specified in the Table 5. The definitions for the Attributes can be found in OPC 10000-3.

Table 5 – Common Object Attributes

Attribute	Value
EventNotifier	Whether the Node can be used to subscribe to Events or not is server-specific.

For all Variables specified in this document, the Attributes named in Table 6 shall be set as specified in the table. The definitions for the Attributes can be found in OPC 10000-3.

Table 6 – Common Variable Attributes

Attribute	Value
MinimumSamplingInterval	Optionally, a server-specific minimum sampling interval is provided.
AccessLevel	The access level for Variables used for type definitions is server-specific, for all other Variables defined in this document, the access level shall allow reading; other settings are server-specific.
UserAccessLevel	The value for the UserAccessLevel Attribute is server-specific. It is assumed that all Variables can be accessed by at least one user.
Value	For Variables used as InstanceDeclarations, the value is server-specific; otherwise it shall represent the value described in the text.
ArrayDimensions	If the ValueRank does not identify an array of a specific dimension (i.e. ValueRank <= 0) the ArrayDimensions can either be set to null or the Attribute is missing. This behaviour is server-specific. If the ValueRank specifies an array of a specific dimension (i.e. ValueRank > 0) then the ArrayDimensions Attribute shall be specified in the table defining the Variable.
Historizing	The value for the Historizing Attribute is server-specific.
AccessLevelEx	If the AccessLevelEx Attribute is provided, it shall have the bits 8, 9, and 10 set to 0, meaning that read and write operations on an individual Variable are atomic, and arrays can be partly written.

For all VariableTypes specified in this document, the Attributes named in Table 7 shall be set as specified in the table. The definitions for the Attributes can be found in OPC 10000-3.

Table 7 – Common VariableType Attributes

Attributes	Value
Value	Optionally a server-specific default value can be provided.
ArrayDimensions	If the ValueRank does not identify an array of a specific dimension (i.e. ValueRank <= 0) the ArrayDimensions can either be set to null or the Attribute is missing. This behaviour is server-specific. If the ValueRank specifies an array of a specific dimension (i.e. ValueRank > 0) then the ArrayDimensions Attribute shall be specified in the table defining the VariableType.

For all Methods specified in this document, the Attributes named in Table 8 shall be set as specified in the table. The definitions for the Attributes can be found in OPC 10000-3.

Table 8 – Common Method Attributes

Attributes	Value
Executable	All Methods defined in this document shall be executable (Executable Attribute set to “True”), unless it is defined differently in the Method definition.
UserExecutable	The value of the UserExecutable Attribute is server-specific. It is assumed that all Methods can be executed by at least one user.