Host Engineering Forum

General Category => ECOMs and ECOM100s => Topic started by: eddie on June 10, 2013, 11:37:00 AM

Title: h2-ecom 100 modbus communications with cognex 7000 series camera
Post by: eddie on June 10, 2013, 11:37:00 AM

I have been assigned a project using 2 cognex 7000 series cameras, with a Automation Direct dl260 plc communicating via ethernet modbus. I have never setup modbus communications before, and dont know where to start.
Any insight as to how to accomplish this would be very much appreciated. A program example that I could study would be great! I forgot to mention that the plc will be the client. Thanks

Title: Re: h2-ecom 100 modbus communications with cognex 7000 series camera
Post by: Controls Guy on June 10, 2013, 11:00:43 PM

You have to use NetEdit to configure slave devices that you will address in ladder using ECWX and ECRX boxes.  InSight allows you to set up what information goes into each register within the camera.

Title: Re: h2-ecom 100 modbus communications with cognex 7000 series camera
Post by: eddie on June 11, 2013, 05:41:11 PM

I have completed the netedit setup for the cameras, and started on the ladder. But I'm having trouble getting the ecrx to accept 50000 for the "from slave element" field. 50000 is the input register from the cognex camera.  Any help would be greatly appreciated!

Title: Re: h2-ecom 100 modbus communications with cognex 7000 series camera
Post by: Controls Guy on June 11, 2013, 06:05:19 PM

Quote from: eddie on June 11, 2013, 05:41:11 PM

I have completed the netedit setup for the cameras, and started on the ladder. But I'm having trouble getting the ecrx to accept 50000 for the "from slave element" field. 50000 is the input register from the cognex camera.  Any help would be greatly appreciated!

You'd probably never talk to another DL PLC using Modbus, but you must still specify the slave starting register address in V-memory terms.  I remember that I've addressed TA0 (which is the same as V0) in Cognex cameras before, which I think would be equivalent to Modbus register 40001.  Try V23417/23420 and that general neighborhood, or try moving the address in the camera.

The "outbound" mapping is the same as the "inbound" used when the PLC is the slave and documented in Chapter 7 or whatever of the manual.  You just have to use the table in reverse.  There's also an Excel spreadsheet for doing the address translation that you can get from Host or ADC.

Title: Re: h2-ecom 100 modbus communications with cognex 7000 series camera
Post by: Greg on June 12, 2013, 08:32:01 AM

eddie, the FAQ that helps explain the mapping is here:
http://www.hosteng.com/FAQFiles/ECOM.htm#FAQ0038 (http://www.hosteng.com/FAQFiles/ECOM.htm#FAQ0038)

...or you can browse to our website (hosteng.com) and in the left column under Support, click FAQs, select ECOM/ECOM100 as the product and scroll down to the FAQ0038. The Excel spreadsheet Controls Guy is talking about is on Automation Direct's website here:
http://support.automationdirect.com/technotes.html (http://support.automationdirect.com/technotes.html)

...it is labeled "AN-MISC-010"

Title: Re: h2-ecom 100 modbus communications with cognex 7000 series camera
Post by: eddie on June 12, 2013, 04:22:08 PM

Gregg
Thanks!! That was EXACTLY what I was needing!