PLC Recommendation

WetShaggy · Jun 29, 2007

I'm getting ready to upgrade a system that has hardware coming end-of-life. The system monitors water pressures and flows. It totalizes flows for hour, day, month and year and looks for "max hours." It is distributed over several square miles and needs to be able to "catch up" if the system loses comms. The current system has a method of easily entering the last known values in the event of an RTU failure that requires reprogramming. Is there any recommendations out there as to what hardware I should use? I'm most familiar with Quantum hardware but I've used quite a few PLCs and RTUs. I've only been working on controls systems for about 18mos.

Thanks in advance.

JesperMP · Jun 29, 2007

It is distributed over several square miles

So there must be some kind of communication system already, and you probably want to reuse it. That could be important for your decision on which PLC to use.
"RTU" could mean that you have fixed or leased modem lines, but how are we supposed to know.
Please elaborate a little bit.

The current system has a method of easily entering the last known values in the event of an RTU failure that requires reprogramming.

Is there an onsite HMI ? Or do you do that remotely ?
Also, how many i/o ?
How many stations ?
How much data ?

WetShaggy · Jun 29, 2007

The current system is using Leased Lines. We do NOT wish to reuse that system as it has not been very reliable. We will use either cell modems or radios.

There are 38 sites.

There are up to 7 pulse inputs, 14 AIs and a few DIs.

We use a laptop that is taken to the site to re-program it. The site has its own program and there is separate 'recipe' file that is use to put the current data back into it. The data is recovered from a SQL database where the reported data is recorded.

The current HMI for this system will be replaced with Cimplicity.

The current systems don't have very much memory in them. I'd need to double-check but it is less than 512KB.

The sites take the pulse inputs and adds them together to create flow totals. There are several runs at each site which are then added together. And those are totaled for the Hour, Day, Month. The program then also records the Highest Hour and its timestamp.
I hope this helps. Thanks again.

Mickey · Jun 29, 2007

Have a look at site below. Excellent product line for your appliication and superior support.

http://www.controlmicrosystems.com/

JesperMP · Jun 29, 2007

To me it sounds like you need some kind of RTU and not a PLC like the Quantum you mention.
RTUs are specialised for this kind of applications. Current types support all kinds of datalogging, webserver and ftp server functionality.

WetShaggy · Jun 29, 2007

Thanks for the suggestion. The ScadaPak was already on our list to check out. Having an outside suggestion is appreciated. I will start with them.

Mickey · Jun 29, 2007

WetShaggy said:
Thanks for the suggestion. The ScadaPak was already on our list to check out. Having an outside suggestion is appreciated. I will start with them.

One more plus for the SCADAPack series of controllers is the programming environment (and instruction set) is very,very similar to Modicon PLC's.
Which would make for a short learning curve for you ( easy transition)

consys · Jun 29, 2007

My two cents worth. I was going to suggest SCADAPAck also. From what I can remeber from their training course they were pretty good at "catch up".

mrtweaver · Jun 29, 2007

My 2 cents worth would be use something like the Horner PLC line. Something in the X series such as the XLE or NX. You save the data to the compact flash then you can access it remotely using FTP or in some cases HTML. As for a nice system for SCADA from all my limited experience I like Inductive Automations Factory PMI and SQL programs. Really quite nice and they work fine. And unlike the Cimplicity which seems quite top heavy to me, it also seems to have problems with keeping the registation. Or so it would seem by the forum under GE.

WetShaggy said:
The current system is using Leased Lines. We do NOT wish to reuse that system as it has not been very reliable. We will use either cell modems or radios.

There are 38 sites.

There are up to 7 pulse inputs, 14 AIs and a few DIs.

We use a laptop that is taken to the site to re-program it. The site has its own program and there is separate 'recipe' file that is use to put the current data back into it. The data is recovered from a SQL database where the reported data is recorded.

The current HMI for this system will be replaced with Cimplicity.

The current systems don't have very much memory in them. I'd need to double-check but it is less than 512KB.

The sites take the pulse inputs and adds them together to create flow totals. There are several runs at each site which are then added together. And those are totaled for the Hour, Day, Month. The program then also records the Highest Hour and its timestamp.
I hope this helps. Thanks again.

PLC Recommendation

WetShaggy

Member

JesperMP

Lifetime Supporting Member + Moderator

WetShaggy

Member

Mickey

Lifetime Supporting Member

JesperMP

Lifetime Supporting Member + Moderator

WetShaggy

Member

Mickey

Lifetime Supporting Member

consys

Member

mrtweaver

Member

Similar Topics