If the text part of a value of DataType is language neutral, i.e. it is the same in all languages, the locale of the 0:LocalizedText should be null or an empty string.

For all 0:LocalizedText that have a language, at least an English version should be provided.

If a type definition in this specification lacks information for a specific scenario, it is possible to extend the type. This is done in a separate vendor specific namespace to indicate that it is outside the scope of this specification. To extend a type, a subtype containing the additional information is created. Instances of this subtype can be used interchangeably with instances of its supertype in the overall Additive Manufacturing node structure of this specification. As the subtyped object needs to contain all information the supertype requires, all clients using this specification can handle the information of the supertype in the subtype. Clients that don’t know the subtype might not use its additional information though.

This specification provides the possibility to indicate changes in the AddressSpace to a client. Most often this concept is used in list representations, to add or delete Nodes from the list. OPC 10000-3 defines the property 0:NodeVersion and the 0:GeneralModelChangeEventType to indicate such changes. Whenever the address space in this specification is changing, the 0:NodeVersion and the 0:GeneralModelChangeEvent shall be used in the way defined in OPC 10000-3.

As content for the 0:NodeVersion property, a timestamp of the moment the node structure was changed converted to a string with the format yyyy-MM-ddTHH:mm:ss.sZ (using UTC time for display) shall be used.

This specification makes use of 0:EngineeringUnits and 0:EUInformation for describing the units of measurement. For this 0:EUInformation applies the UN/CEFACT “Codes for Units of Measurement” and maps the codes to OPC UA: http://www.opcfoundation.org/UA/EngineeringUnits/UNECE/UNECE_to_OPCUA.csv. In the context of this specification only engineering units according to Table 12 should be used.

Table 12 – Engineering Units Recommendations

UnitId

DisplayName

Description

UNECE Code

5066068

mm

Millimetre

MMT

5067858

m

Metre

MTR

4804168

in

Inch

INH

4607828

ft

Foot

FOT

4933453

kg

Kilogram

KGM

4674125

g

Gram

GRM

4997714

lb

Pound

LBR

5197402

oz

Ounze

ONZ

5002322

l

Litre

LTR

5065812

ml

Millilitre

MLT

5067857

Cubic metre

MTQ

4410705

cm³

Cubic centimetre

CMQ

4408652

°C

Degree Celsius

CEL

4604232

°F

Degree Fahrenheit

FAH

4342098

bar

Bar (pressure unit)

BAR