Lookout or DSC?

[Phil Duncan]

I am investigating options for developing a SCADA type system that includes remote monitoring/control of PLC's. I have been reading all about SCADA, LabVIEW DSC, NI Lookout, PAC's vs PLC's etc. It seems that this sort of project can be completed using LabVIEW DSC but it looks like this may be the low level approach. Does NI Lookout simplify the process enough to justify the cost? Will LV DSC allow me to do everything I need?

Your advice is most welcome.

Cheers & Beers

:thumbup: & :beer:

[i2dx]

I am investigating options for developing a SCADA type system that includes remote monitoring/control of PLC's. I have been reading all about SCADA, LabVIEW DSC, NI Lookout, PAC's vs PLC's etc. It seems that this sort of project can be completed using LabVIEW DSC but it looks like this may be the low level approach. Does NI Lookout simplify the process enough to justify the cost? Will LV DSC allow me to do everything I need?

Your advice is most welcome.

Cheers & Beers

:thumbup: & :beer:

I am aware that I could drop in a brick with this advice. I don't know anything about Lookout, but I had a longer phone call with a colleague yesterday and he was complaining a lot about the quality of the DSC Module. It seems to be a Module which is not used very often, and therefore full of bugs, etc ... so my adavice would be: get a trial version of the DSC Module and try to implement the mission critical parts with DSC to see if you can reach your goal with this module.

[Syd Chasm]

Hi Phil.

I started out interfacing Labview to PLC's when the Bridgeview package was still around - all this really was was labview with an OPC interface added to the toolbox. With Labview 8's OPC interface, you can access data from your PLC without any additional toolboxes provided that you have an OPC client running somewhere on your network (for example, RSLinx if you're using A-B PLC's) - the only real additional benefit that you'll get from using DSC/Lookout are some animated graphics of pumps and vessels and some pre-written alarm management vi's (which were not very good quality in the days of Bridgeview, I have not opted for DSC for a long while now so I don't know how much added functionality there is).

Having said all of that, my view is that Labview beats the pants off of SCADA packages like Wonderware and Intellution FIX DMACS in terms of programmability and flexibility, and I would certainly go for a Labview development environment to interface to a PLC everytime.

It may well be worth looking into using Fieldpoint real time rather than a PLC depending upon your application. If there is a strong safety critical element, then a PLC is still the better option because you can opt for multiple redundancy, SIL ratings and even ATEX-ratings if needed. The fact that Fieldpoint Real Time gives you an OS independant of windows has gone a long way towards making it a competitive technology with PLC's, but as the market stands today a properly engineered PLC system will still have a much lower failure rate than what you can achieve with a PAC. That said, I have found applications where Fieldpoint real time was a batter option because I could code some high bandwidth multi-variable controllers in Labview real time that would have simply been impossible with a PLC - it comes down to the sophistication of G against the languages available to PLC programmers, as well as the instrumentation heritage of NI products in terms of fast data acquistion.

I guess that your optimal choice of technology is strongly dependant upon your application - if it's a simple SCADA with a couple of screens of operator GUI and a simple alarm handler, then I'd say use FIX or Wonderware as this is well within their limited functionality. If you're looking to do some clever supervisory or statistical control with calculations & data passing between the client PLC's, or if you're looking to interact with a database using SQL, or automatically populate Word or Excel reports, then Labview will pay for itself very quickly.

Would be interested to hear if other developers share my views on this!

Good Luck,

Syd

(ps - you can also use third party drivers to talk to your PLC's - e.g. http://www.softwaretoolbox.com have some decent products. Also, beware of using serial comms as the update time via OPC can be very slow. Ethercat, Fieldbus or DH+ will give you faster updates).

I am investigating options for developing a SCADA type system that includes remote monitoring/control of PLC's. I have been reading all about SCADA, LabVIEW DSC, NI Lookout, PAC's vs PLC's etc. It seems that this sort of project can be completed using LabVIEW DSC but it looks like this may be the low level approach. Does NI Lookout simplify the process enough to justify the cost? Will LV DSC allow me to do everything I need?

Your advice is most welcome.

Cheers & Beers

:thumbup: & :beer:

[Rolf Kalbermatter]

Hi Phil.

I started out interfacing Labview to PLC's when the Bridgeview package was still around - all this really was was labview with an OPC interface added to the toolbox. With Labview 8's OPC interface, you can access data from your PLC without any additional toolboxes provided that you have an OPC client running somewhere on your network (for example, RSLinx if you're using A-B PLC's) - the only real additional benefit that you'll get from using DSC/Lookout are some animated graphics of pumps and vessels and some pre-written alarm management vi's (which were not very good quality in the days of Bridgeview, I have not opted for DSC for a long while now so I don't know how much added functionality there is).

Ouch! LabVIEW DSC is a bit more than OPC access, which in the days of BridgeVIEW was quite limited, and alarm management. Things like integrated event and realtime logging, a complete tag based data engine and completely networked and very fast data exchange between engines is quite a bit more than just some simple cosmetics. I do know how hard these things are as I implemented in the past a system similar to what BridgeVIEW had been although not exactly as complete as BridgeVIEW.

That said LabVIEW DSC has some issues with things not always working perfectly, partly due to the rather complex system it has grown, partly due to various technology changes in the past from an almost entirely in LabVIEW written SCADA package (BridgeVIEW 1.0) to a system where quite some parts moved out of LabVIEW and parts of the Lookout SCADA engine where integrated instead in LabVIEW DSC 6.0 to a system where virtually everything important is done by various components outside of LabVIEW with quite some of them inheriting from the Lookout technology (LabVIEW DSC 7 and 8). This frequent change of architecture introduced its problems where with each new major version completely new subsystems got replaced and with it new bugs that needed their time to be ironed out, only to introduce other new bugs with the next major architecture change.

You can build quite powerful and interesting SCADA applications with LabVIEW DSC as I have used BridgeVIEW 1.0, 2.0, and LabVIEW DSC 5 - 7 for some projects and they always did what had to be done, although there were occasionally some problems to debug and to resolve in more or less close cooperation with some developers in Austin.

Lookout in itself has therefore all the features LabVIEW DSC has and a few more except the highly programmable LabVIEW environment. It seems NI is not pushing Lookout anymore but has no intentions of abandoning it yet. The problem with Lookout is not that it is a bad system (it is absolutely not). But when you create a Lookout program you are not exactly programming but rather configuring your application, but this configuration is very powerful the way it is done. The real problem why it never got a big success is twofold. NI had LabVIEW which is sexy and powerful and the NI sales force had little knowledge about Lookout and little interest to learn it since selling LabVIEW was easier and had a lot more sex appeal.

Without LabVIEW and the will from NI to go after the SCADA market, Lookout could have easily gotten the killer app in the NI SCADA product line.

One of the reasons why I didn't push Lookout myself more for any of our projects was the much more involved licensing for distributed apps in comparison to LabVIEW applications that we could make. But to be honest for classical SCADA applications that certainly wasn't a problem. Lookout was quite cheap in comparison to most other SCADA packages out there back in the late 90ies.

Rolf Kalbermatter

[Phil Duncan]

Thank you all for your excellent input.

I will let you know which way we go and will no doubt have lots of development questions/bugs to iron out in these forums.

Cheers & Beers

:thumbup: & :beer:

PS. I hope you are celebrating Australia Day Chris!

[crelf]

PS. I hope you are celebrating Australia Day Chris!

My bloody-oath I am!

Download File:post-181-1169732419.zip

Although it's not quite my normal Australia Day of jumping on the motorbike, heading down to the Sydney fish markets early in the morning to grab a couple of kilos of king prawns off the trawlers as they come in, a few fresh crusty bread rolls, a six pack of tinnies, and then back on the bike over to Maroubra beach to enjoy my traditional breakfast on the sand. It's -15degC here in Michigan, and there's a couple of inches of snow on the ground - my commute home last night averaged 6 miles an hour, and included one period of travelling north while the car was pointing east...