Time Synchronization between S7-400 and WinCC OA

[vla]

Is there a way to get the time from S7-400 PLC and set it to the computer where WinCC OA is running on? The computer is running on 64-bit Windows 7 Professional, a common off the shelf Dell Computer.

I know there is a way to send the time from WinCC OA to the PLC, but not the other way around. Please help.

Thanks in advance.

[Gertjan van Schijndel]

It is not a good idea to change the time on the computer, where WinCC OA runs on. WinCC OA does not like time changes. If you set the clock backwards, you cannot set datapoint elements, that have a newer timestamp. If you set the clock forward you can get a bunch of timeout messages in the log.

By setting the S7 config entry 'ReadPLCTime = "Y"', the driver will read out the time of the plc and write it to the '.Time.Value' dpe.
However there is no standard function available to set the time of a computer.

[aorange]

That sounds like a bad idea... get your computer time synced with an NTP server (online, domain controller or SICLOCK) and synchronise your PLC to the PC.

Otherwise what are you going to do when you add a second PLC to the network?

[leoknipp]

Hello,

normally the computers (where WinCC OA is running) and components (for a WinCC OA system) are time synchronized by an external program/software. It is recommended to use a time synchronization. The source for the time can be dcf-clock or a time-server.
A PLC is never used as a time server.
In some cases the time synchronization of the PLCs with WinCC OA as time master is used. If a PLC shall be synchronzed the datapoint-element "_S7-connection-DP".Time.SyncTime is set. Therefore it can be done for every PLC on its own.


Best Regards
Leopold Knipp
Senior Support Specialist

[vla]

Does not matter if I add a second PLC to the network as I am always get the time from one PLC only, the others are not of my concern.

The configuration I have right now is my PLCs are all synchronized to the same time server. However, my workstations do not have direct access to this time server, so in order to time synchronize all PLC's and PC's, I can only get the time from the PLC somehow... Anyone knows if there are other ways to work this out? Thanks!

[vla]