Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Ethernet for Industrial I/O

Status
Not open for further replies.

Fchild

Electrical
Mar 23, 2004
11
I have a project coming up. I have four machines with Rockwell VFDs on them. I want to monitor the speed of the drives of the drives for trending and such. One solution was to hook up a simple 4 pen chart recorder to the A/O of the drives. This would require that someone change the paper in the charts and collect the charts every couple days. I would like a more eligant solution. Of course I have very little money to spend. I would like device that would take in an anolog sygnal and put it out on the eithernet so that my IT guy can program me a nice little spread sheet of the data. I would guess he would DDE or what ever to get the data. Can anyone point me to a vendor that would have some info on a device like this?
 
Replies continue below

Recommended for you

Doing this is not going to be so cheap, what existing control automation equiipment have you got in the area.


This is a link to a VIPA PLC manufacturer that is very inexpensive and you get good value for money, its configuration software is Step 7 from Siemens...

If you dont want to go 4 a PLC here is a link to another option...


I would reccomend the PLC option, it gives you room for future expansion on the automated side of things, this is a dedicated controller without expansion capabilitys...

Regards

RHeinhardt

--Off all the things i've lost , i miss my mind the most--
 

This will get you pretty close. If you can get a converter to locally convert the analog output to any type of serial output, there are alot of serial-to-ethernet converters available.

Are you sure you can't get a serial port from the VFD and just skip the analog part?

Try some Google searches and see what you come up with. I'd guess you could get this for under $500/point, maybe a lot less than that. Not counting the Ethernet wiring and the 80 man-hours you'll spend on that Excel spreadsheet.

I wouldn't even think about a pen recorder. If I never see one of those again, it will be too soon.

Good luck.
 
This is a motion controller with a Ethernet interface. It also has a free OCX that allows one to control or montior the motion controller from VB or Excel. However, Excel is NOT meant to be a control program. More importantly the controller will connect to the RSLinx so you can also use your RSView or other Rockwell compatible products.
 
Hi guys:

Perhaps I don't understand the whole scope, I think one option could be this cheap module from
The problem is the serial conection to the closest pc, but for $25, solves the main goal. Now, If it is required conectivity to ethernet, then is possible use serial ethernet converters.

Hope helps


Freddy Guedez
Shenandoah Engineering Services
 
Elegant and little money do go together.
Fchild hasn't specified the whole scope. The dataq data logger would record analog data but at what resolution or data acquisistion rate? Second, what is the type of data that Fchild is trying to record? Is this data streamed continously to the PC or PLC? I would want to record the postion/speed with a quadrature encoder or absolute encoder depending on the application. The output of the drive will be a chopped up analog signal that will be almost meaningless. It would be better if the drive had a analog signal that had the effective control signal. If that isn't available then it would be nice to read the output value right out of the drive over the ethernet.

The motion controller above would control the 4 VFDs as well as acquire data and is Ethernet/IP certified so it is compatible with other Rockwell products. Yes, it cost more but it does more and will not be a kludge. Controller can produce status data a 5 millisecond intervals that any consumer can record. This is done all the time but rarely does anyone want to log the data because there would be too much.
 
I think Peter is right here, Fchild hasn't specified the whole scope. It would really help if had some more info.

Are the four machines stand alones with separate controllers, and are they networked, or are all part of a single system?

What type of controller(s) and communications is used with the drives?

What model of Rockwell drive is used?
 
OK, thanks guys. I will try to define this a little better. I am looking to grab speed information from the drives. The data is not being used for control but just for analysis. I will need a sample about every 30 seconds or so. I so far have four seperate machines that are not networked. They are stand alone systems. One has a SLC5/04 on it. That will be the prototype. I have done some research since my first post and found that we have some software and hardware in the mill that is not being used.
We have a fully fuctional PI server and I recently got our RSLinx data collector going. The only part that I am stuck on is getting the rslnix data collector to talk to the PI server. The process guys are familar with PI and once the tags are configured can build there own screens and such.
I will establish eithernet connection to one rslogix 5000 processor in the area and link the other PLCs together wiht remote i/o and bring the data to one centeral plc in that department. I can then connect to the plc with our rslinx data collector PC and get the data into PI. This will give me way lots of storage and allow me to trend all kinds of usfull stuff from the drive system for maintanance and stuff.
Total cost=
Cat5 and conduit $1000
electrician labor $2000
maybe an engineer to help with the set up of the dcomm for the rslinx server to the pi server.

 
oops i meant to say a SLC5/05 with eithernet.
 
You can send the data directly to Excel, using rslinx as the server. search the help files in RSlinx. I set up this interface in about 2 minutes. It was very easy to do.
search for DDE TOPICS and automating Excel etc..

best regards, PLCSAVVY
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor