ECN Forum Forums General Topics of the Trade General Discussion Area PLC control topics

Hi all we run every line in our plant with PLC’s. I only allow AB products because of the following; quality, tech support, common platform to learn, ease of programming. And the list could go on AB/Rockwell in my area with the local supply house have many free hands on and lecture sessions through out the year. I attend many the one thing I see is that its mostly plant guys like me. I think that systems integration is a growing field and many electricians are missing out on the opportunity. In western MA there are only a handful of outside resources available. When talking to contractors I urge them to learn all they can or to pick one of their guys and get him/her some training. If you look at upfront cost it may be more but you need to look beyond that a well designed system is much more flexible for future changes and installation costs can be lower that with pipe and wire. AB’s website has lots of good info its worth a visit. If any one has specific questions I’ll monitor this thread and try to reply.
http://www.ab.com/
http://www.software.rockwell.com/

I think PLC's are becoming critical for today's electricians (industrial electricians in paticular)to understand them and be able to troubleshoot PLC controlled systems. I attended a 2-week course in Oregon on the GE Fanuc about 6 years ago. Two years ago I attended a 2 week course on Omron's and likewise on Allen-Bradley. Next....well there's always ABB to go to school on. But my point is that the best way to learn, in my opinion, is by virtue of being an industrial electrician and getting daily, if not hourly experience on production/maintenance support calls. I think it is going to be tough for the "average" commercial electrician, let alone residential, to work with them consistently enough to gain proficiency with PLC's. This experience would obstensibly come under controls, as in controls technician, or industrial automation technician.

to golf junkie:
I do understand what you means , but I think that the PLC's price are coming down and different PLCs have very great difference Price. as I know that, PLC made in US are most expensive, I suggest you can choice some PLC made in Japen or TaiWan or some others else, their prices are much cheaper but the quality are good too. I think that Omron, Nais,mitsubishi should be considered.
as you konw that , it will be a smart electircal panel if you uesed PLC in a motor control system.

Hi Stanley,

I'm an electrician at a large OSB (orientated strand board) factory in northern Minnesota. This factory originally used mostly Square D and TI PLCs (circa 1980), but all but one TI system have been replaced now with Allen Bradley PLC-5/30 and 60 series processors using ICOM software. We will be converting over to RSview soon. Operators control using panelview touch screens, and windows NT/2000 based PCs using controlview.

We also have many Allen Bradley frequency drives throughout the plant. Every processor, freq drive, and programming node is linked together via data highway. The processors message one another throughout the process via this data highway. All of this new technology is tough for an old geezer like me to learn!

Matt

Hello everyone,
I am learning and working with PLCs everyday. I work with them both at school and work. I was just wondering what kind of programming techniques some of you have seen. Such as how interlocks or anti-tie downs are programmed in for instance. We were taught in school that some places will program completely different and that even some engineers will program so that it would take a rocket scientist to figure out what they've done. The way it looks to me that PLCs or some sort of computer automation is the way industry is going. We are even learning at work the Allerton system which is full building automation. Pretty neat stuff.

Chris, there are as many ways to tie interlocks as there are programmers but I will relate my experiences to you. On anti-tie downs we use a timer to make sure that the buttons must be made and opened. Use the ENABLED bit to allow the program to step and the DONE bit to make sure the buttons are not taped down. On interlocks we usually have them inserted in the AUTO operation rung so the machine will not go into operation with an unsafe condition. PLC's sure beat having to meter 30 or so relay contacts to see where the problem is, besides we use a PC to troubleshoot them so I get to play on a computer and get paid for it! Almost criminal isn't it!

[This message has been edited by spkjpr (edited 03-28-2002).]

i once worked for rockwell for about 18 years. the plant was fully automated state of the art equip, at the time. about the time rockwell 'merged' with ab we were installing a new excello fms. so, of course the controls were all ab products. there were 4 plc 3/10's, 2 plc 3's, 4 plc 2's, 18 8600cnc controlled machines, 5 data line displays, 2 asea robots and an advisor monitoring system. all the machines had 6 ac servo drives and a dc spindle drive. and believe it or not the machine ran 80% of it's production. my point here is, with over 8000 i/o you need to know plc's to find that one faulty prox switch.
now there is technology that enables a system like this one to run on a regular pc with built in diagnostics.
plc's are well worth your wild to learn.
thx., ken m

Just found this post and thought I’d respond. I work at a car assembly plant and we (electricians) assist production by trying to figure how to keep assembly lines running. We use A/B PLC’s (5/20’s, 5'40’s, and 5/80’s) to control the operations of our automated lines. We use ICOM software. The PLC is a great trouble shooting aid. Surprisingly a lot of electricians in our plant do not want to use them. I don’t know if they are intimidated by them or what? The company has trained all of us on how to program and trouble shoot. But it takes a lot of practice and hard work to become proficient at it. I personally love using them and use them all the time. Many times it is the only way a problem can be found in a quick and timely manner.

The A/B training and manuals are very expensive! Stanley did your company reimburse you for the manuals you have or did you pay out of your own pocket?

[This message has been edited by MikeW (edited 06-09-2002).]

[This message has been edited by MikeW (edited 06-09-2002).]