NET_ENIs Communication Limitations Net Eni Net-Eni ML1500

Hello Everybody,

I am working on a system that is made up of 3 ML1500's (LRPs) connected to NET-ENIs and 3 PanelView Plus 1000's (Touch, Ethernet, Serial). I will be configuring the HMIs to talk to the LRPs over serial to free up Ethernet Connections.

The PLCs need to talk to each other over Ethernet for status and some interlocks (heartbeats will be done correctly).

There will be a PC running FT Historian and RSLinx pulling a dozen analog values from each PLC.

There will be a second PC running RSLinx G/W pulling status from the 3 PLCs to a Foxboro I/A system.

I am concerned about the number of connections through the NET-ENI's. In fact, I am pretty sure the communications will lock up.

PLC A Read and Write message instructions to PLC B uses 1 outgoing connection in PLC A Net-Eni and 1 incoming connection in PLC B.

PLC A Read and Write message instructions to PLC C uses 1 outgoing connection in PLC A Net-Eni and 1 incoming connection in PLC C.

Not taking into account the Historian, Foxboro or programming connections I only have...

2 incoming and 2 flexible connections in PLC A.
1 incoming, 2 outgoing and 2 flexible connections in the PLC B
1 incoming, 2 outgoing and 2 flexible connections in the PLC C

So, this will not work, I am pretty sure as soon as someone opens RSLinx on the Engineering Work Station to go online, I will run out of incoming connections on PLC A.

Questions...

I am looking for an alternative to the NET-ENIs that can handle more connections, does a product exist?

Are my connections calculations correct?

Sadly, I can not go to Compact, Control or ML1400 or ML1100.

Best regards to the group!

Paul

If you can replace your 1500 go ahead, net eni are a pain in the neck. I have replaced all of them either with ML1400 or ML1100.

widelto said:

If you can replace your 1500 go ahead, net eni are a pain in the neck. I have replaced all of them either with ML1400 or ML1100.

Click to expand...

Thanks for the reply, but sadly, I can not change the PLCs.

Check DigiOne IAP.

mcfarlde said:

Check DigiOne IAP.

Click to expand...

Thanks, that was on my radar. I need to investigate the differences between RS-232/422/485 (IAP) and DF1 Net-Eni.

I assume the IAP will require ladder to complete the link?

The IAP should work in place of the NET-ENI.

They are about half the physical width of the NET-ENI. The free software for managing them over ethernet works just fine. I am not sure that the performance will be better but I have heard others say that they're faster. Also, I am not sure about the number of connections they support, or if there is even a comparable specification.

The only thing we haven't been able to do with them is to pass through the PLC to download to a panelview standard on CH1 of a 5/03. I am not even sure the NET-ENI can do that.

The setup of the Digi is straightforward. Give it an IP address, bring up its web page, and enter the username and password.

Then you just set the serial port protocol to what you want and away you go. We use "DF1 Full-Duplex". Serial Slave or Serial Master both seem to work for what we're doing, so I haven't read up on the differences there. Also, you have to set the baud rate under Basic Serial settings. I don't think they support autobaud.

It's also a good idea to add the eds file to RSLinx. Then, you'll see the SLC on your ethernet drive and the Digi IAP will be transparent, unless the SLC dies or its serial port is unplugged and the Digi is still up and running, then your icon will switch to the Digi icon in RSLinx. This makes for simple troubleshooting.

Digi gives you a device discovery program that will find and list all the digi products on your subnet for easy management.

The NetENI can handle only 4 connections and sometimes hangs because of duplicates to same address.

Type the ethernet address of the NetENI into a web browser to see diagnostic tab

For the price of a NetENI you can buy a ML1100 and you end up with far better ethernet performance .
I agree with Widelto on his views.

OkiePC said:

The IAP should work in place of the NET-ENI.

They are about half the physical width of the NET-ENI. The free software for managing them over ethernet works just fine. I am not sure that the performance will be better but I have heard others say that they're faster. Also, I am not sure about the number of connections they support, or if there is even a comparable specification.

The only thing we haven't been able to do with them is to pass through the PLC to download to a panelview standard on CH1 of a 5/03. I am not even sure the NET-ENI can do that.

The setup of the Digi is straightforward. Give it an IP address, bring up its web page, and enter the username and password.

Then you just set the serial port protocol to what you want and away you go. We use "DF1 Full-Duplex". Serial Slave or Serial Master both seem to work for what we're doing, so I haven't read up on the differences there. Also, you have to set the baud rate under Basic Serial settings. I don't think they support autobaud.

It's also a good idea to add the eds file to RSLinx. Then, you'll see the SLC on your ethernet drive and the Digi IAP will be transparent, unless the SLC dies or its serial port is unplugged and the Digi is still up and running, then your icon will switch to the Digi icon in RSLinx. This makes for simple troubleshooting.

Digi gives you a device discovery program that will find and list all the digi products on your subnet for easy management.

Click to expand...

Wow, thanks OkiePC! All great information, and promising!

Gil47 said:

The NetENI can handle only 4 connections and sometimes hangs because of duplicates to same address.

Type the ethernet address of the NetENI into a web browser to see diagnostic tab

For the price of a NetENI you can buy a ML1100 and you end up with far better ethernet performance .
I agree with Widelto on his views.

Click to expand...

Thanks for the reply. I was reading that the Net-Eni can support 2 in, 2 out and 2 in/out connections. So you could have 4 in 2 out, or 3 and 3 or 2 and 4.

Would love to change the PLCs, but I am stuck with the 1500's. I wanted an L43, but was shot down by the customer. Must be 1500. Also 1100/1400 will not handle the I/O count.

Thanks again!

do yourself a favor and replace the net eni with a digi one iap, might save some heartache and a job.

I also have an application where i have to send ASCII characters to an inview display over the ethernet. I have a NET-ENI connected to channel 1 of ML1500 to set up communication between the ML1500 and my inview display and to the rest of the network.

The problem.
in order to send messages in ascii commands from the plc to the inview we need to configure the port as ASCII. (do I get this right)
I tried this approach but no luck. the PLC through the NET-ENI could no longer communicate with the nerwork.

Until now the problem still exist, we could not get our inview to display the variables that we need to display. hi guys, do yuo suggest that i use a IAP instead of a NET-ENI or does anybody out there know of a cheaper solution. I would appreciate any help you can offer

If you set the port for ASCII, that's all it will do. No RSLinx/Logix through serial, no NET-ENI, just ASCII.

You could use a protocal converter to handle the messaging. This sounds like a great fit for a Red Lion G3 or data station. It's not the cheapest, but is very easy to set up. If you already have an HMI on the machine, you could replace it with a Red Lion G3, and let the G3 drive the ASCII commands to the Inview, leave the SLC set up for DF1 connected to the NET-ENI.

A G3 with ethernet can talk to the SLC through a NET-ENI with no problem (I just set the Device Identification settings for the SLC in Crimson 3 to "ENI / Micrologix"), and creating gateway blocks (or perhaps a fairly simple G3 program) to automatically retrieve data from the SLC and send it out one of its serial port as ASCII should be pretty easy to do.

Pompey
If you have a ML1500 LRP you have 2 port available for RS232
The ML 1500 LSP only has 1 RS232 port

The red lion G3 might be a great idea we are strapped on the budget. I am contemplating on using my RsView32 to drive my INVIEW display through the ethernet. I was wondering if this is all possible. Has anyone tried this or is this just a shot to the moon.

RSView32 can use an activeX control to write to an Inview display. I read that in a technote at ab.com. I have not used the activeX control, but you should be able to find more info there.

I also ran across this thread that might be of interest to you:
http://forums.mrplc.com/index.php?showtopic=19783