You are not registered yet. Please click here to register!


 
 
plc storereviewsdownloads
This board is for PLC Related Q&A ONLY. Please DON'T use it for advertising, etc.
 
Try our online PLC Simulator- FREE.  Click here now to try it.

---------->>>>>Get FREE PLC Programming Tips

New Here? Please read this important info!!!


Go Back   PLCS.net - Interactive Q & A > PLCS.net - Interactive Q & A > LIVE PLC Questions And Answers

PLC training tools sale

Reply
 
Thread Tools Display Modes
Old November 29th, 2017, 02:42 PM   #1
curlyandshemp
Lifetime Supporting Member
Canada

curlyandshemp is offline
 
curlyandshemp's Avatar
 
Join Date: Jul 2005
Location: Toronto
Posts: 1,873
Two 1756-L72 -> One 1756-EN2T-> Ethernet IO

just need to convince myself what I am doing is OK.

Have a project where I am splitting up the process into two 1756-L72 CPUs on an A10 rack. I will have two 1756-EN2T Ethernet modules, one for IO and the other for HMI and plant SCADA.

There will be several 1734 Point Ethernet IO drops throughout the plant. Each L72 will 'own' its 1734 drop but share the same 1756-EN2T Ethernet module. I realize all 1734 Ethernet IPs must be unique and on the same subnet, and only 1 CPU can 'own' a drop.

This is feasible?
__________________
Work to Ride,
Then Ride to Work

I would rather have a bottle in front of me..
than have a frontal lobotomy
  Reply With Quote
Old November 29th, 2017, 04:00 PM   #2
ASF
Lifetime Supporting Member
Australia

ASF is offline
 
Join Date: Jun 2012
Location: Australia
Posts: 2,635
I've never done that specifically, but I can see no reason it wouldn't work.
  Reply With Quote
Old November 29th, 2017, 04:08 PM   #3
Ken Roach
Lifetime Supporting Member + Moderator
United States

Ken Roach is offline
 
Ken Roach's Avatar
 
Join Date: Apr 2002
Location: Seattle, WA
Posts: 14,104
I have done this sort of multi-CPU network module sharing with both EtherNet/IP and ControlNet networks.

As long as the 1756-EN2T has enough connection capacity and CPU capacity to handle the volume of data going through it, it can serve I/O connections and messaging for multiple controllers in the backplane.

One thing you can't do is put the CPU in a backplane that has to go over a ControlNet or EtherNet/IP bridge and then back out through another ControlNet or EtherNet/IP bridge before getting to the I/O adapter. That's not what you are proposing, but I figured I'd bring it up in case you get tempted.
  Reply With Quote
Old November 29th, 2017, 06:13 PM   #4
curlyandshemp
Lifetime Supporting Member
Canada

curlyandshemp is offline
 
curlyandshemp's Avatar
 
Join Date: Jul 2005
Location: Toronto
Posts: 1,873
Quote:
Originally Posted by Ken Roach View Post
I have done this sort of multi-CPU network module sharing with both EtherNet/IP and ControlNet networks.

As long as the 1756-EN2T has enough connection capacity and CPU capacity to handle the volume of data going through it, it can serve I/O connections and messaging for multiple controllers in the backplane.

One thing you can't do is put the CPU in a backplane that has to go over a ControlNet or EtherNet/IP bridge and then back out through another ControlNet or EtherNet/IP bridge before getting to the I/O adapter. That's not what you are proposing, but I figured I'd bring it up in case you get tempted.
OK, thanks.

I have done this before using CNET, just have not used EtherNet/IP based IO.
__________________
Work to Ride,
Then Ride to Work

I would rather have a bottle in front of me..
than have a frontal lobotomy
  Reply With Quote
Old November 29th, 2017, 07:18 PM   #5
Ken Roach
Lifetime Supporting Member + Moderator
United States

Ken Roach is offline
 
Ken Roach's Avatar
 
Join Date: Apr 2002
Location: Seattle, WA
Posts: 14,104
The nice thing about EtherNet/IP for this application (compared to ControlNet) is that you don't have to re-schedule the network when one controller adds or modifies it's I/O tree.
  Reply With Quote
Reply
Jump to Live PLC Question and Answer Forum

Bookmarks


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Topics
Thread Thread Starter Forum Replies Last Post
Distributed IO control over Ethernet - Siemens Profinet g18c LIVE PLC Questions And Answers 5 June 30th, 2014 05:39 PM
Losing IO config over Ethernet rixer LIVE PLC Questions And Answers 8 April 23rd, 2011 07:21 PM
Generic Serial or Ethernet IO ihc LIVE PLC Questions And Answers 2 February 8th, 2007 03:27 AM
GE Fanuc Ethernet Remote IO Question jimbo3123 LIVE PLC Questions And Answers 3 January 31st, 2005 02:12 PM
Profibus ---> Ethernet Prince LIVE PLC Questions And Answers 1 January 2nd, 2004 01:31 AM


All times are GMT -5. The time now is 11:13 PM.


.