1756-EN2TR DLR Config

[raamakoti]

Hello Everyone,
What is the best practice for DLR set up. Should I keep all VFDs on one DLR and FlexIO on another or it would make sense to put all of the devices on one DLR.
The DLR consists of below hardware.
FlexIO - enet modules 14 with IO count of less than a 1000
VFDs - 20 mix of 525 and 70s with 20-comm card
PLC - 1756-L83EP

Thank you for your help
Raama

 

[A_G]

Im not sure, but this doc may help
https://literature.rockwellautomation.com/idc/groups/literature/documents/at/enet-at007_-en-p.pdf

 

[Contr_Conn]

DLR recommended max number of nodes is 50.
However there is a EN2TR bandwidth limit of now many packet per second it can process. I would recommend to enter the actual RPIs into the IAB to make sure you are not exceeding capacity.

Also keep in mind that DLR can tolerate only one fault. With so many nodes, the chance of second fault is significantly higher.
What if you need to remove a couple drives for maintenance? Any devices between them will lost comms too.

Personally, I would use smaller, more resilient rings, but your situation may be different.

 

[JeremyM]

20-COMM-E cards aren't capable of being in a DLR in the first place.

Are you just trying to use both ports of the EN2TR?

 

[tlf30]

The 25-COMM-E2P support DLR.
For me I would consider if the VFDs were to be powered down. Powering down the VFD will be a break in the ring, so if you only ever need to power down a single drive then all is good.

Edit: not sure on the PF70s with the 20 cards, those will probably not be able to be on the ring without ETAPs.

 

[stretch_af]

IMHO, The processor/ENBT, Switches and any remote I/O on the DLR.
VFDs use star topology of a switch.

 

[Jmeadows7676]

VFDs - 20 mix of 525 and 70s with 20-comm card
:

I normally don't put VFD's on DLR if there is any possibility that more than one Drive can be off at any giving time. This would isolate or island some of the Drives.

 

[raamakoti]

DLR recommended max number of nodes is 50.
However there is a EN2TR bandwidth limit of now many packet per second it can process. I would recommend to enter the actual RPIs into the IAB to make sure you are not exceeding capacity.

Also keep in mind that DLR can tolerate only one fault. With so many nodes, the chance of second fault is significantly higher.
What if you need to remove a couple drives for maintenance? Any devices between them will lost comms too.

Personally, I would use smaller, more resilient rings, but your situation may be different.

Thank you all for your responses. We have 14 FlexIO we definitely want to put on DLR. The plan is to upgrade all the ControlNet module to EtherNet. There a lot of legacy hardware that we want to upgrade. FlexIO controlNet module will be replaced with 1794-AENTR and old ENBT will be replaced with EN2TR. VFDs with controlnet modules will be replaced with EtherNet modules, bit cheaper than replacing the VFD. or as VFDs fail then replace them with EtherNet capable drives.
Also I was not planning to go from VFD to VFD as part of DLR. I wanted to add a stratix as part of DLR and connect all drives through that. This way I wouldn't have to worry about breaking the ring with offline VFDs. Would it be a good solution?

 

[cidchase]

I personally like to use the ETAP to prevent breaking the ring. Just my opinion!
It is critical if one is a backup.