6.13 MDISTimeSyncObjectType

6.13.1 Introduction

In some systems, a MDIS Server might be on an isolated network, one in which there is no NTP or other source of time synchronization signals. In these systems, the MDIS Server would need to be able to obtain a minimum time synchronization signal from the Client. This ObjectType and associated method is designed to allow this minimum time synchronization. It should only be used if a better time synchronization system, such as NTP, is not available. The accuracy of this type of time synchronization could be in the range of seconds.

If this Object is supported, a single instance of this Object shall exist on a Server. The Object shall have a name TimeSynchronization and the instance shall exist as part of the MDISInformationObject.

6.13.2 Overview

The following section details the MDISTimeSyncObjectType. This optional type allows a Client to provide time synchronization information to a Server. The Client can call the SetTime Method periodically to ensure the Server time does not drift. This Method does not return until the time on the Server has been updated or an error is returned.

6.13.3 MDISTimeSyncObjectType Definition

Table 84 defines the structure of an MDISTimeSyncObjectType.

The current time on the Server is available as part of the ServerStatus provided by all OPC UA Servers.

SetTime – This method allows a Client to set time on the Server.

6.13.4 SetTime Method

SetTime Method (defined in Table 85) is used to set the time on the Server. If an error occurs this Method shall return an error code indicating the failure to set the time (see Table 87).

Signature:

	SetTime (
		[in] 0:UtcTime TargetTime );
	

Method result codes are defined as part of the Call Service (see OPC 10000-4). They are described in Table 124 for ease of reference.

Comments

The SetTime Method will change the time on the Server. Table 86 specifies the AddressSpace representation for the SetTime Method.