ControlNet Lowdown

TimeFluxCap

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Join Date
Nov 2002
Location
Australia
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321
Hi guys

I have my first ControlNet I need to support on site and have never used ControlNet before.

Its a ControlLogix system with its second IO rack connect to the main rack by ControlNet cards.

I have the program for the CPU, but am I also meant to get the RSNetworx for ControlNet file as well?

From other posts I have read you setup the ControlNet cards with RSNetworx but exactly what is done here?

Any info would be great!
 
Ah, yes Crocop, I have gathered that and I have the software. Do you use a backuo file of the config though is more along the lines of what I am asking.

Also in RSLogix5000 when you look at the properties of the ControlNet card there is a link too RSNetworx, what is this used for?
 
You will need both RSNetworx for ControlNet and RSLogix 5000 on your computer to commission the system.

The *.ACD file for the controller program and the *.XC file for the network do by default reside in different directories, but they are tied together by RSLogix 5000.

You can tell RSLogix 5000 where the configuration file for a particular ControlNet segment is, and the two programs will share connection data. "Scheduling" the network is little more than a press of a button in RSLogix 5000 to kick off RSNetworx and run it through the scheduling process (Edit Mode, Calculate Schedule, Download Schedule, Download Keepers). All you have to do is click "OK" and be ready for the controller to go into Program Mode during the scheduling process.
 
Originally posted by TimeFluxCap:

Also in RSLogix5000 when you look at the properties of the ControlNet card there is a link too RSNetworx, what is this used for?

This is the beauty of RSNetworx and Logix5000. As Ken said, the two are tied together. The file name you put in the path is used to store the CNet config data. When you do a save, Logix5000 examines your Logix5000 I/O configuration and updates the RSNetworx file with the appropriate data based on the I/O layout. When you are ready you use the link you refer to to initiate a CNet scheduling, as Ken said. This really does work pretty slick. I have never had any problems getting a CNet network set up when I have triggered the process from Logix5000. If you've ever done DeviceNet you will absolutely love ControlNet. It is significantly easier to use the data.

Keith
 
Sounds like I need to ge tthe .XC file for the ControlNet config off the developer then.

Thansk guys, I think I will have a couple more questions but thats all I need for now.
 
OK here is my next question


Can you upload a schedule from the system? Also, if I can browse the CNB card by going though a ENBT then backplane to it, can you still upload it?

Or do you have to have the .XC file?
 
Yes
Yes (but it'll be a tiny bit slower)
NetworX CN essentially forces you have .xc file; give it a meaningful name though, DO NOT accept the default. I've seen so many guys overwrite files that they didn't really mean to because if this.
 
TimeFluxCap said:
Can you upload a schedule from the system? Also, if I can browse the CNB card by going though a ENBT then backplane to it, can you still upload it?Or do you have to have the .XC file?
Yes, you can upload schedule.
Actually sometimes it's the only way if offline XC file does not work
- Download Ladder in Logix5000
- Open RSnetworx
- File -> New, Online, Upload from the network
- Edits Enable, VErify network properties
- File -> Save AS, Optimize and re-write.
This will schedule network.
 
Another hardware note

- make sure you installed taps and terminators - direct cable will not work.
- make sure node numbers start with 1 and no skips.
- Media length, SMAX and UMAX set correctly in network properties.
 
Hi Guys:

I just learned controlnet by myself this week and this is what i did:

- First you have to have the rslogix 5k and rsnetworx for control net
- set up your controlnet hardware according to your necesities
- the 1756-cnb should have address 1 on controlnet in order to be the keeper
- the 1756-cnb has to be /d or can not be the keeper
- the rpi for the 1756-cnb/d has to be 0, the rest on the control net is going to manage the rpi according to you necessities
- the fastest way to handle comm is to separate the discrete i/o board from the analog boards.
- set up comm for discrete boards as rack optimized
- setup rpi discrete 10 mS
- setup comm for analog boards as input/output data
- set up rpi for analog boards at 50 mS or greater
- do not leave spaces on your addresses, begining with 2 up to the maximum of scheduled data
- there is no unscheduled or schedules hardware i use these words just to identify what kind of comm thery are going to use.
- then continue with unscheduled hardware normally hmi's, that means that if your scheduled hardware end at address 22 the unschedules hardware must be 23 and higher.
- set smax 2 numbers higher than max scheduled hardware
- set umax 4 number higher tha max unscheduled hardware
- do not forget that the maximum number of connections for the 1756-cnb/d is 64
- each rack full of discrete boards count as one conection
- each analog board count as a connection
- download your software to yor clx processor, previously you have configured rslinx.
- start rsnetworx for controlnet
- co to conection and let the rsnetworx upload the configuration you didi on the rsligix 5k
- the go to network on the and there configure umax and smax
- a good number for nut is 10 mS
- save the file on your computer
- download this file to you network and controlnet is configured
- i believe i included everything.
- a good site where to learn tips is a cd from automation fais and look for tutorial for rslogix 5k optimization.

william delatorre
 
Widelto; first thing to say is that you've done really well to get a ControlNet system by teaching yourself. The second thing to say is that many things that say show that you've taught yourself. The things that I feel I must correct are:

- set up comm for discrete boards as rack optimized
...unless you've bought those expensive Diagnostic series I/O or you want different RPI rates for some of the modules.

- set smax 2 numbers higher than max scheduled hardware
- set umax 4 number higher tha max unscheduled hardware
...it's not that simple; if you've got a CLX CPU with two chassis of I/O then 5 is a poor choice for Smax, you're wasting bandwidth.

- the 1756-cnb should have address 1 on controlnet in order to be the keeper

... you're right to make a CNB Node 1 if it's a choice between it and a Drive, but not because the keeper has to be Node 1; thats a misconception based on the "bad old" PLC5/ControlNet days

But finally:
- do not forget that the maximum number of connections for the 1756-cnb/d is 64

If someone who has taught themselves can find out that there's a connection limit through a CNB why do so many other people miss it? Widelto, well done!
 
Comment on previous post by widelto:

- CNB in the local chassis has no RPI - no such thing as RPI=0

- If remote rack has only analog or diagnostic modules with direct connections, set CNB Comm.Format to NONE, do not use Rack Optimization.

- CNB does not have to be node 1, it can be any node. Lowest keeper capable node will be the keeper. For example CNB in redundancy chassis can't be node 1 or 2.

- SMAX must(!) be equal to the highest scheduled node

- 64 connections via 1756-CNB/D are unreachable it is in the range of 40s. I am not sure if 1756-CNB/E released, but it will have similar performance I think. New 1756-CN2 can reach 64 connection easily.
Use 1756-CN2 in the processor chassis.
 

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