Preserving time stamps from the publishing source

The following configuration examples do not preserve the original time zone. That is, if you want to pass only the time stamp, the subscriber gets the time stamp as converted to the local time zone of the publisher and not the time zone of the data source.

Example 1:

PLC.Item <= GalaxyA Object1.IntAttr.Time <= Gateway <= GalaxyB OPCClient <= Object1.TimeAttr

GalaxyB:Object1.TimeAttr shows the time adjusted to the local time zone of the GalaxyA Gateway Communication Driver and not the time zone of the PLC.

Example 2:

PLC.Item <= GalaxyA Object1.IntAttr.Time <= InTouch App I/O Message Tag <= GalaxyB InTouchProxy <= Object1.TimeAttr

GalaxyB:Object1.TimeAttr shows the time adjusted to the local time zone of the InTouch application and not the time zone of the PLC:

To preserve the Time Stamps

To avoid these problems and preserve the time stamps, subscribe to the GalaxyA:Object1.IntAttr value property. Both the value and time stamp propagate to GalaxyB:Object1.IntAttr. You can then use the GalaxyB:Object1.IntAttr.Time.

For example:

PLC.Item <= GalaxyA Object1.IntAttr <= Gateway <= GalaxyB OPCClient <= Object1.IntAttr

PLC.Item <= GalaxyA Object1.IntAttr <= InTouch App I/O Integer Tag <= GalaxyB InTouchProxy <= Object1.IntAttr

In the following configuration, the time property propagates from InTouch to Object.IntAttr.Time:

PLC.Item <= InTouch I/O Integer Tag <= Galaxy InTouchProxy <= Object.IntAttr