VFD Comm
VFD Comm
(OP)
I am implementing motor controls in a new treatment plant, that consists of a variety of VFD's, Soft Starters, and across the line starters. Since this is a new plant, I am considering using communicating with my VFD's and soft starters using Ethernet/IP rather than the digital and analog PLC I/O that I typically incorporate.
I am concerned about the reliability and the operation of motor control I/O, as I seem to remember an issue in the past, in which VFD's ended up dumping gobs of data onto the network and were responsible for data collisions, and generally bogging down network traffic.
Can anyone direct me to a web site that reviews and/or compares the VFD's of different manufactures, with particular interest in the Ethernet communication feature?
Would anyone like to comment on their experience communicating to drive from their plant PLC via Ethernet?
Thanks for your input.
Paul
I am concerned about the reliability and the operation of motor control I/O, as I seem to remember an issue in the past, in which VFD's ended up dumping gobs of data onto the network and were responsible for data collisions, and generally bogging down network traffic.
Can anyone direct me to a web site that reviews and/or compares the VFD's of different manufactures, with particular interest in the Ethernet communication feature?
Would anyone like to comment on their experience communicating to drive from their plant PLC via Ethernet?
Thanks for your input.
Paul





RE: VFD Comm
Roy
RE: VFD Comm
Cheers,
Mort
RE: VFD Comm
Benta.
RE: VFD Comm
Profinet:
http://www.profibus.com/pn/
Sercos:
http://www.sercos.com/
Profinet is certainly becoming more popular in automation, particularly in Europe.
Cheers,
Mort
RE: VFD Comm
FYI, Ethernet/IP is basically Devicenet over Ethernet.
RE: VFD Comm
Profibus is much more widely supported but you will need to be aware of network lenghths and number of nodes per network limitations.
Matt
RE: VFD Comm
Easiest way to go is use a punch down box and then use a patch cable off the shelf from the punch down box to the drive.
Connections from past comms systems
Devicenet is easy to terminate
Controlnet has a predefined connection system kit
Profibus, siemens makes a vampire type connector that is pretty idiot proof and a stripping tool also.
Ethernet - looked at this one and do not see an idiot proof way except the one presently described above.
The other thing that you need to look at is the patch cable provided are straight or do you have to provide a cross cable?
RE: VFD Comm
RE: VFD Comm
I doubt speed is an issue unless you were doing something like a paper machine, even RS-485 is fast enough for most applications.
Roy
RE: VFD Comm
RE: VFD Comm
But you are hijacking your own thread which means that people who may have the answer to this question may never see it as they decided this thread didn't require further input from them or wasn't of interest. Different questions deserve different threads.
Keith Cress
kcress - http://www.flaminsystems.com
RE: VFD Comm
Check your PLC's on site. If you have A-B, then Devicenet might be better or if Siemens then Profibus. Others will have both.
If you are worried about the integrity of your communications, keep it simple.
RE: VFD Comm
Sorry but FrischEng was actually repeating a question asked in his OP. It seems to have been missed as the thread has developed. It's strange how these things evolve
FrischEng: I've been looking for some comparison data without success, I think you need to assess each system against your current (and future) requirements. It sounds like a fairly complicated installation, it might be a good idea to get all the hardware from the same manufacturer - I would imagine that any support you may need would be easier that way.
Cheers,
Mort
RE: VFD Comm
Modbus, Modbus plus and Profibus are daisy chain so all your cables need to be OK whereas Ethernet would be Star if that makes a difference.
Something else to consider is troubleshooting tools, is it easier to communicate with a laptop (or terminal) to one over the other?
How will you configure the drives, from a PC or individually.
Do you have a control system picked out yet?
I would do a spreadsheet listing all the options, advantages, cost etc.
Interesting thread, keep us posted.
Roy
RE: VFD Comm
Keith Cress
kcress - http://www.flaminsystems.com
RE: VFD Comm
What drives were they that you had the problems with? The current Siemens stuff now has the fieldbus integrated into the control unit, no external boxes required. Certainly, the issue you describe wouldn't get through system test and type test nowadays (hopefully).
Cheers,
Mort
RE: VFD Comm
You may also need to consider your Emergency Stop system. Only a few drives from CT & SEW have "Safe Stop" inputs. We opted for an ASi-Safe network sitting below and communicating status up to the Profibus.
I would second ScumPunk by saying get all the major kit from one maunfacturer, otherwise when you ask for support, they will just blame the other vendors eqp. We learnt the hard way!
Matt
RE: VFD Comm
Not sure if you are aware, but there is an ET200 VFD module available with full Safety Integrated functionality (Safe stop, Safe ramp down, Safe Low Speed). Power modules are 0.75W-4kW, and it plugs on to the back plane, along with the rest of the ET200 kit. Sounds like it may be the ideal solution for your application. I'm really sorry if I sound like a salesman, apologies if this is the way it looks.
Link:
htt
Cheers,
Mort.
RE: VFD Comm
Though the downside of this was having twice as many profibus nodes on the network, one for each drive and one for each remote i/o header.
Matt
RE: VFD Comm
My drives were Siemens MidiMaster 1 - 40HP with a clip on module 6SE3290 for the Profibus.
I had 10 drives and 5 PLC racks on the same network.
It worked really well except for the Hang-up after a power fail.
I suspect it was my driver.
Regards
Roy
RE: VFD Comm
There is an IP65 ET200 drive available (just released), but I think it's a max. of 1.5kW. It was developed in parallel with the G120D distributed "standalone" drive - up to 7.5kW, IP65. The MM4 range are gradually being superseded by the Sinamics range, which are a significant step forward. Again, apologies for sounding like a salesman.
Roy, thanks for the reply, no problem, I'm sure everyones busy (except me, first week off this year
Cheers,
Mort
RE: VFD Comm
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