Installing and communicating with a Remote I/O from 7 miles away

geoffewart

Member
Join Date
Jul 2012
Location
St. Croix
Posts
7
Hi all,

We're looking to install a remote I/O to interface with some pumps (Max of 4) and instruments (Max 6 for now) at a pier 7 miles from our main facility. The site at the pier has power but little else though there is the possibility of adding internet to the site if that will make integrating easier. We have a couple of Controllogix PLCs and assorted goodies (ethernet/IP, Devicenet, and Profibus comms) here at the main facility. The other option we have is that we have a spare Controllogix PLC and modules that we could install at the pier but we have concerns about security with the value of that.

The communications if it is wireless will have to contend with travelling directly over the airport, a couple industrial facilities and the fact that the pier is an active cargo pier with a container port, customs, warehouses etc.

So my questions are:

Firstly, remote I/O or remote PLC?

How to communicate with either selection? I've done some searches on radios here but haven't been able to find a response I'd be comfortable betting the farm on for our application.

We also have Square D Powerlink lighting panels that are networked in here at the facility and are hoping to be able to tie the lights down at the pier in remotely?
 
IM not a pro with wireless links but to me it sond better to put a local plc doing the basic and emergency task and let the remote control happening by the control room thru communication and if this communication is lost, at least the local plc would continue...VS remote i/o that would be just crashed until communication get back...
This way you need a good communication but not the best of the best...

I mention it because my experience with wireless wasn't perfect...
 
id definitely have a remote plc to handle safety/control. you can use a few different methods to communicate back and forth. cellular is one option(digi connectwan), another would be a radio shot(GE INET).
 
+1 for dedicated PLC setup. We commonly use 3G modems to access our equipment when it's on site. The only downside is that you have to deal with a telecomms company who usually charges an arm and leg for a Data only SIM.


With a PLC at the pier, how often would you need to send data back and forth from the main facility?
 
Thanks for the responses, sounds like a remote PLC is the safer option.

Jeev - we'd probably want to send/receive data from the pier every couple minutes for the instruments as not much happens there, but when a pump is running it would need to be more frequent. One of the pumps serves as a mixer for a tank there and we'd like to be able to mix that tank remotely from the main facility
 
Hello
why not use an SMS Relay module?
use a contact in your local plc program and you would be able to communicate with the plc through GSM Network
 
Thanks for the responses, sounds like a remote PLC is the safer option.

Jeev - we'd probably want to send/receive data from the pier every couple minutes for the instruments as not much happens there, but when a pump is running it would need to be more frequent. One of the pumps serves as a mixer for a tank there and we'd like to be able to mix that tank remotely from the main facility


My only concern would be how much data is actually being exchanged and what your Service provider is going to charge you. Our most common use is remote troubleshooting over 3G, so we're only ever connected for short periods of time and never use up the 1-2Gb we have. We are also using Pre-paid SIMs, so you can monitor the usages online and top up when you need to.

The alternative would be to set up your own high-powered wireless network ($$$ even with 10km LoS), but with the given obstacles and the fact most of them cause noise; it may be with limited success and reliability.

Don't forget to put some code in your Pier PLC, so that it polls a heartbeat and if comms is lost to the Main Facility then you can shut down any dangerous or critical operations at the Pier. A loss of communication resulting in incorrect control should always leave the plant/machine in a safe state whether it's running or faulted.

I just fault our stuff and bring it all to a grinding halt, so the operators are more inclined to get the network issue fixed.
 
The site at the pier has power but little else though there is the possibility of adding internet to the site if that will make integrating easier. ... The other option we have is that we have a spare Controllogix PLC and modules...

have you thought any more about the 1756-EWEB module that Daren and I were playing around with in the lab? ... if you were to plug one of those into a ControlLogix chassis out at the remote site, you could communicate with it via Internet ...

if you're interested in experimenting with one, let me know and I'll set it up at the lab ... once I give you the password and IP address, you should be able to set up a few data points to monitor and to control – just by using Internet Explorer, etc. ...
 
honestly Ron that EWEB module is probably our first choice right now, we were hoping to be able to avoid putting the PLC at the pier but it does make sense from a safety standpoint. So now in that case I think that getting an internet connection and that module is going to be the easiest, most reliable way to set up
 
I'll be heading up to the lab in the next couple of hours ... I'll set it up and email you the password and the IP address ... you can try it out all weekend if you like ...
 
this should let you control it from 7 thousand miles away ...

Greetings Geoff ...

I've emailed you the EWEB module's IP address – and the password ...

just play around with it as much as you like ... I plan to dump everything out of it anyway next week sometime so don't worry about messing anything up ...

the figure below should give you some basic guidance ...

I programmed a "down and dirty" control and feedback arrangement for four pumps just so that you could see that you're actually controlling something in the ControlLogix processor ... I'm attaching a printout of the program to the next post ...

basic idea: type TRUE to put a one into the COMMAND bit and click UPDATE to tell the pump to come on ... the real-world output should fire ... that's wired back to a real-world input ... the real-world input is programmed to write a one into the RUNNING bit for confirmation from the field ... the "PUMP_IS_RUNNING" bit should change to TRUE ...

check the addresses in the program printout ... I didn't take time to "line up" the input and output wiring – so the bit addresses are assigned in "random" fashion ...

feel free to experiment and set up your own Data Views and see how they work ... just be SURE to type the tag names EXACTLY the way they're set up in the program ... (Ethel isn't here to help you with this part of the puzzle) ...

hope this helps ...

.

EWEB_SCREEN_SHOT_2.PNG
 
Last edited:

Similar Topics

A new point I/O rack is to be hooked up with the running PLC. In point I/O, it is supposed to be the OA4 card to be installed as per the...
Replies
1
Views
75
During the process of installing Studio 5000 Mini Edition to my new machine at work, it seems as though some things like RSLinx Classic and the...
Replies
3
Views
438
Hi All, I haven't installed Unity Pro in years and needed to install it recently. I initially tried installing Version 11.1 and the whole...
Replies
3
Views
631
Hi all, I tried to install Twidosuite on windows 10 but after installing i have the registration link which is not working and also i get with...
Replies
0
Views
559
I completely uninstalled Wonderware 2020 and all the related components, rebooted, and then tried to install InTouch 2012, but it won't proceed...
Replies
9
Views
1,996
Back
Top Bottom