Clock Synchronization

Is there an application that may run on a 2000 server with Many A/B PLCs on ethernet (SLC, Mlogix, PLC 5, ControlLogix) to set the clock directly in the PLCs. Or is there any sample code for VB? Thanks..

You aren't using an HMI?

Using a TOP server to log data directly in InSQL. There is no HMI application in between.

How accurate do you need them all to be? For example, it could take several seconds to write all the PLCs -- so their times would differ by several seconds.

Do they need to be accurate to official US time? You can write code that gets the official US time (see http://www.time.gov).

It is easy to write a program to write a value, in this case time, to each PLC. Depending on the PLC you can write directly to each PLC's time memory storage, or wether you need to write to another location and then set a flag so PLC ladder logic reads the value and sets the time.

It does not need to be very accurate. Do you know of any suggested code? (VB?). Writing the clock values from an application to a IP based PLC.

Thanks..

Couldn't you use a scheduled job in the database to push NOW() through InSQL to each PLC?

Just a short SQL script for each PLC to take current time, format it properly, and push it to the PLC's. For Microsoft SQL Server, you can use the SQLServerAgent to schedule the jobs in the Database itself. Just use a daily schedule to push the times out.

How would wrote from SQL directly to a PLC? Do you have a code example?