Changing IP address on existing Powerflex 753 VFD

[jrterry]

Hello, I am being told by IT to set new IP addresses for many devices, starting with some VFDs and later PLCs. Is this as simple as changing the IP address with the keypad on the VFD, and in the settings of the PLC? Will the PLC programs that use VFD tags need modified or will they see the changed IP address?

[IO_Rack]

If the VFD is being controlled by the PLC then no, if will not be that easy. The PLC has a very specific network configuration that allows it to control the VFD, and likely other devices such as remote I/O, vision inspection systems, weighing scales, etc...

It can be done but it would need to be planned out. I'm guessing these devices are on your corporate network? If so, is IT trying to isolate these devices from the corporate network? That would be a good plan.

[jrterry]

1 hour ago, IO_Rack said:

If the VFD is being controlled by the PLC then no, if will not be that easy. The PLC has a very specific network configuration that allows it to control the VFD, and likely other devices such as remote I/O, vision inspection systems, weighing scales, etc...

It can be done but it would need to be planned out. I'm guessing these devices are on your corporate network? If so, is IT trying to isolate these devices from the corporate network? That would be a good plan.

Part of a plant SCADA upgrade, they are wanting to change IP addresses for security reasons. So could someone tell me how I would make these changes without breaking everything? Is there a way to change the IP in one spot and everything follow suite or is it going to be more complex than that?

[IO_Rack]

21 minutes ago, jrterry said:

Is there a way to change the IP in one spot and everything follow suite

No. Each device will need to be changed and each may have a different method. 

Without knowing all the manufacturing devices on your network, and the structure, it's difficult to say. My guess is, it's going to be more complex than that. 

I would highly recommend that you talk to your Rockwell distributor and have them consult with your IT department on a plan. Changing the IP addresses is one thing but putting the machines on a separated network is important (IMO). Maybe your IT department has that in mind in this upgrade but they need to understand the machine networks as well. 

How many PLCs do you have? How many other manufacturing devices do you have that require IP addresses? Do you have a network diagram?

[Joe E.]

I'm with @IO_Rack here.

Honestly, if you have that many devices, I would very seriously consider going a different route. Use some managed switches or NAT devices or something to do the routing but physically isolate the networks with a single, tightly controlled bridge for the SCADA systems. I'm thinking about what I would go through changing the IP addresses on just one of our systems and it would be a huge undertaking. It would likely take most of a day at least, with the system down completely throughout the process. Personally, I would have each system or subsystem on its own physical network with very strategically placed connection points. For example, if you use ControlLogix PLCs, add a network module on the IT network and SCADA systems but have all of the PLC and its devices on its own physical network (or networks) through another network module. It gets more complicated with older CompactLogix PLCs that only have one connection, but that's where routing and NAT come in.

Also, all the IP addresses of a PLC and all of its controlled devices will need to be changed together, unless you're really clever with subnetting.

[jrterry]

On 1/14/2025 at 7:28 AM, Joe E. said:

I'm with @IO_Rack here.

Honestly, if you have that many devices, I would very seriously consider going a different route. Use some managed switches or NAT devices or something to do the routing but physically isolate the networks with a single, tightly controlled bridge for the SCADA systems. I'm thinking about what I would go through changing the IP addresses on just one of our systems and it would be a huge undertaking. It would likely take most of a day at least, with the system down completely throughout the process. Personally, I would have each system or subsystem on its own physical network with very strategically placed connection points. For example, if you use ControlLogix PLCs, add a network module on the IT network and SCADA systems but have all of the PLC and its devices on its own physical network (or networks) through another network module. It gets more complicated with older CompactLogix PLCs that only have one connection, but that's where routing and NAT come in.

Also, all the IP addresses of a PLC and all of its controlled devices will need to be changed together, unless you're really clever with subnetting.

We have approximately 30 PLCs, and 8 drives. They are all remotely located whether at our water treatment plant or one of our wells located around town, or a water tower. We are upgrading to new PLCs and IT has given me a list of IP addresses they want me to use for the new system, and I was told to go ahead and change the IP addresses of the drives. Seems like I could get into a mess really quickly with this. I'm still pretty green behind the gills.

[Joe E.]

The magnitude of the mess will depend on the degree of interaction between the devices. A PLC that just interacts with the SCADA won't be an issue, but a PLC that manages a handful of drives, 2 other PLCs, and the SCADA will all have to be changed at the same time. And that part of the system will be down for the duration.

That's assuming, of course, that the new addresses are on a different subnet. If you're just spreading them out in the same subnet they're currently in (like moving from 192.168.1.10 to 192.168.1.80), then you can do them piecemeal. If you're going from 192.168.0.x to 192.168.1.y, you may be able to use subnet masks to keep them together but if you're going from 192.168.1.x to 10.130.249.x, you can't.

As @IO_Rack mentioned, a network diagram will go a long way towards planning this. It should show not just the devices and their addresses but comm links among devices. It's definitely worth spending a day or two creating it.

[jrterry]

We are doing a test with a VFD. I changed the IP on the VFD and in the PLC that it communicates with. I believe there is an issue with the IPsec tunnel that IT is using, but they are working on it. In the mean time, I changed the name in the PLC of another VFD that was poorly labeled and it resulted in loss of communication to that VFD. I reverted the name to what it was previously called and it fixed it. Does the device get named in the HIM, and then that name must match what you call it in the PLC? 

It was arbitrarily named something like e-275 and I changed it to its real name, HSP-2. I had to change it back to e-275 to reestablish communications. 

[IO_Rack]

1 hour ago, jrterry said:

Does the device get named in the HIM, and then that name must match what you call it in the PLC? 

The name should not matter outside of the PLC program. The PLC configuration gives it a name in the program for tagging purposes, but regardless, what you are attempting will not work.

 

On 1/13/2025 at 12:30 PM, IO_Rack said:

The PLC has a very specific network configuration that allows it to control the VFD

 

[jrterry]

How do I tell what CIP the plc and drive is using? I assume both the drive and the PLC it’s communicating with need to both be talking CIP1 or CIP3?

[IO_Rack]

Do you mean Class 1 vs Class 3?

Class 1 is "Implicit" communications. Using RSLogix 5000 or Studio 5000 (depending on the version), Look under I/O Configuration > Ethernet. Here you may find the PowerFlex. The programmed name will follow the model number. Find the name in the Controller Tags. The names will be followed by "I:x" and "O:x". This data is exchanged cyclically. Meaning, this data is exchanged at a rate set by the RPI setting.

Class 3 is "Explicit". This is a Command and Response form of communication. In AB PLCs, this will be performed via a MSG instruction. The Communication tab of the MSG instruction will contain the path of the PowerFlex in some cryptic format. 

Both are possible in the same program. Most likely, they are communicating Class 1. 

PowerFlexes aside, take note to all the devices you see in the Ethernet project tree. If you change the PLC IP address, all these devices will be affected. 

[BobLfoot]

Just an example.  I have 180 Scada PCs, 85 PLCs and 300 or so VFDs and HMIs spread of six buildings and 3.5 miles of campus.  My IT department has been working with me since COVID hit to redo a network segmentation.  We are 75% complete with a final target date in 2026.  So even if it takes you a while take heart it can be done if you build the right plan with the right team.