Time Sync problem (Rockwell Automation)

[MHamza1998]

I have a problem with time sync working in this topology.
I have a plc with grandmaster clock controlling motion groups. I wanted to add kinetix 350 to the local network of the seconed plc.
I enabled the time synchronization in the seconed processor but it sees the first one as the grandmaster and i can not control the drive .. after removing the ethernet cable from the first plc the drive worked well. But i still need the connection of the first plc to the network.
ANY HELP ?!

 

[JeremyM]

What PLCs are involved?

Is time sync not working or is the PLC IO connection itself not working?

 

[MHamza1998]

Both are control logix
The drive is the device that is not working , it sees the plc with the grandmaster clock as it's master , and not the seconed plc it's connected to it

 

[kekrahulik]

Is Time Sync Enabled on the 2nd PLC? Is it the system master? (see Date/Time tab on processor properties)
Same question for the 1st PLC
Is CIP Sync Time Synchronization enabled or disabled on the two ENET cards?

 

[MHamza1998]

The time sync is enabled on both PLCs , 1st PLC is the master.
The ENET Card connected to the servo has the time sync enabled , but on the ENET connected to the first plc is disabled

 

[kekrahulik]

My memory is a little foggy, but I did fight something like this a few years ago.

I think the solution resides in the Controller properties / Date-Time Tab / Advanced screen. You need to adjust the priorities of the controllers. I think you want to make the 1st PLC lower priority than the 2nd PLC (not 100% certain, but i think so)

EDIT - see next reply

 

[kekrahulik]

Actually - reverse that. Make 2PLC priority a lower number. Smaller number = higher priority

 

[muusic_man]

Put a NAT on the second PLC ethernet. This will prevent it from seeing the first PLC and it can act as it's own time sync. I have a huge network across 17 buildings and several PLC's have servos. All that have servos have a NAT for this very reason because if the second PLC can't see the first one of the syncing is delayed, the servo stuff is extremely sensitive to this.