News:

  • July 01, 2026, 07:23:05 AM

Login with username, password and session length

Author Topic: Modbus/TCP Server problems  (Read 45905 times)

Controls Guy

  • Internal Dev
  • Hero Member
  • ****
  • Posts: 3619
  • Darth Ladder
Re: Modbus/TCP Server problems
« Reply #30 on: April 16, 2015, 01:05:20 PM »
Contemporary Controls also have this 5-port switch that doesn't learn what IP's are accessible via which port and just sends all traffic down all ports.

http://www.ccontrols.com/ctrlink/eiskd.php

To me, that's a hub, but Contemporary Controls still calls it a switch with that one exception.  Not sure what the difference is.

Because of that, you can run NetEdit to a PLC on the other side of this switch.  There are systems where you wouldn't want the message flooding, but in some systems it wouldn't hurt anything and allows you to NetEdit the PLC without temporarily rewiring.
I retract my earlier statement that half of all politicians are crooks.  Half of all politicians are NOT crooks.  There.

BobO

  • Host Moderator
  • Hero Member
  • *****
  • Posts: 6164
  • Yes Pinky, Do-more will control the world!
Re: Modbus/TCP Server problems
« Reply #31 on: April 16, 2015, 01:09:04 PM »
The distinction is likely that unlike a hub, it caches and resends, allowing source and destination to be different speeds. Functionally speaking, it does sound like a hub...which is a very useful thing.
"It has recently come to our attention that users spend 95% of their time using 5% of the available features. That might be relevant." -BobO

Controls Guy

  • Internal Dev
  • Hero Member
  • ****
  • Posts: 3619
  • Darth Ladder
Re: Modbus/TCP Server problems
« Reply #32 on: April 16, 2015, 01:22:29 PM »
Yup.  They call it a "diagnostic" switch, so they're targeting the kinds of things like troubleshooting protocols where neither device is a PC; same types of things we were talking about with the Netgear switch earlier up the thread.  Difference being that this one is industrial style and quality.  DIN rail, 24VAC/VDC power via terminals, etc.
I retract my earlier statement that half of all politicians are crooks.  Half of all politicians are NOT crooks.  There.

Controls Guy

  • Internal Dev
  • Hero Member
  • ****
  • Posts: 3619
  • Darth Ladder
Re: Modbus/TCP Server problems
« Reply #33 on: April 16, 2015, 10:23:28 PM »
Oops, thought my December post was about Contemporary Controls' EIPR router, so today's post was meant to supplement that.  (I'll delete the December one, as I've actually tried NetEdit over the switch now and know it works) Their router is also a very cool product and likely applicable to what a lot of forum users do. 

I've tested so I can leave the PLC and HMI addresses fixed and route through the plant network leaving the WAN side as a DHCP client, and the PLC can send emails and so on.  Here's the router page:

http://www.ccontrols.com/ctrlink/eipr.php

I retract my earlier statement that half of all politicians are crooks.  Half of all politicians are NOT crooks.  There.