The LockingServicesType provides the Methods needed to lock or unlock. Figure 34 shows the LockingServicesType definition. It is formally defined in Table 54.

image037.png

Figure 34 – LockingServicesType

Table 54 – LockingServicesType definition

Attribute

Value

BrowseName

LockingServicesType

IsAbstract

False

References

NodeClass

BrowseName

DataType

TypeDefinition

ModellingRule

Subtype of the BaseObjectType defined in OPC 10000-5.

HasComponent

Method

InitLock

Mandatory

HasComponent

Method

RenewLock

Mandatory

HasComponent

Method

ExitLock

Mandatory

HasComponent

Method

BreakLock

Mandatory

HasProperty

Variable

0:DefaultInstanceBrowseName

QualifiedName

PropertyType

HasProperty

Variable

Locked

Boolean

PropertyType

Mandatory

HasProperty

Variable

LockingClient

String

PropertyType

Mandatory

HasProperty

Variable

LockingUser

String

PropertyType

Mandatory

HasProperty

Variable

RemainingLockTime

Duration

PropertyType

Mandatory

The StatusCode Bad_MethodInvalid shall be returned from the Call Service for Objects where locking is not supported. Bad_UserAccessDenied shall be returned if the Client User does not have the permission to call the Methods.

The DefaultInstanceBrowseName Property – defined in OPC 10000-3 – is used to specify the recommended BrowseName for instances of the LockingServicesType. Its Value is defined in Table 55.

Table 55 – LockingServicesType Additional Variable Attributes

Source Path

Value

Description

0:DefaultInstanceBrowseName

Lock

The following LockingServices Properties offer lock-status information.

Locked when True indicates that this element has been locked by some Client and that no or just limited access is available for other Clients.

LockingClient contains the ApplicationUri of the Client as provided in the CreateSession Service call (see OPC 10000-4).

LockingUser contains the identity of the user. It is obtained directly or indirectly from the UserIdentityToken passed by the Client in the ActivateSession Service call (see OPC 10000-4).

RemainingLockTime denotes the remaining time in milliseconds after which the lock will automatically be timed out by the Server. This time is based upon MaxInactiveLockTime (see 8.3.4).