PLC

Google: "industrial project on plc" and you will find plenty of homework suggestions.

What is a "critical program"? What is "greatful"? Who is "u"?

High resolution optical pattern recognition for the purpose of automated separation of fly excrement from ground black pepper.

Be easy on the poster. He is either a student or someone like myself who is trying to learn on his own.

I remember years ago, when I first got my hands on a PLC. I had the advantage of knowing traditional relay ladder logic and machine language computer programming, so learning to program one of these critters was, to me intuitive. My challenge was to learn how to apply the power of this device, in an efficient way, to real world problems that I encountered in my work.

If I have been successful in this , it is because of the help and guidance from people like you. There is no better teacher than to look at and analyze someone else's program. It is amazing what can be learned from a few simple suggestions, and constructive criticism

By the way, I am neither an electrical engineer, nor an electrician. I am a tool and die maker who morphed into a machine designer. I learned to program PLCs because it was easier than trying to explain to an electrician what I wanted my design to do.

Yup,i'm a student.dng 3rd yr B.E

People always used to say that,everyelectrical engineer should complete plc before course completion.But our financial status is not tat much to join that course.thats y I'm trying to study it on my own.And i finished learning ladder diagram,and also have done some simple projects like..traffic signal with night mode,multiplexer,etc..

Padupoi,

How about this one: A generic sewage lift station or water tower level control. The inputs will be either an analog signal for the level, or up to 6 float switches for low alarm, high alarm, and pump on/off control. It needs to include alternation of lead/lag pump, detection of defective or failed float switches, selection of analog/discrete level control by use of an internal bit, and the ability to work in stations with 2 or 3 pumps and constant or variable speed motor controls. Its outputs need to be on/off control of each pump, analog output for variable speed control (if used), and outputs for remote status and alarm condition monitoring via a SCADA system. This will not be a new application, but will give you good experience in an application that uses some good programming skill.

If you want to go further, explore how such a program could be written in various PLC programming languages as defined by IEC standards.

--JMM

Thanks a lot sir,definitely it means a lot to me.

Hi

You or someone are over complicating the lift station controls and the VFD controls with PLC. Don't need the complicated and expensive PLC for a reliable dual pump control or one Settable PSI control VFD driven pump. Let Me help You to design one for You. (Removed telephone number and email address) I do work on Volunteer basis, just pay My expense, I don't charge anything, I just like to do something.

I modify 126 lift station before I Retired and six booster pump VFD control ,which maintaning 80 PSI or any setting You want. For give Me the spelling. Call if You want an very experienced lift station control guy.

Sir,

There is merit to your complaint about over complicating the lift station controls... An equally valid argument could be made about reliability of the controls in a relay-only station. Just as your suggestion was based on your experience, mine was based on real-life experience in a utility with over 25 sewage lift stations (ranging from a few hundred gallons per day to a half-million gallons per hour) and a number of water pressure boosting stations. We had found that the controls (including alternator relays, flow-matcher salt baths for wound-rotor motors, and custom programs or hard-wired relays that were different for each and every station) were all a maintenance and trouble-shooter's nightmare. It took us about 2 years to standardize the lift station controls to a single "generic" PLC family and program, capable of being applied to any lift station we had by either setting a few internal bits permanently ON (or OFF) or by a few jumper wires on certain PLC inputs. The big advantage this gave us was the ability to recognize and intelligently respond to conditions that would have been unrecognized disasters to the relay-only system. Reliability, troubleshooting, repairs, and supervisory control were greatly improved.

That experience was the reason for the suggested program in my earlier post.

With respect--JMM

Sir

The PLC is very good and important patr of the industrial automation. But not neede for any duplex pump list station control or one or two VFD pump control. For lift station I used a easy to set(by screwdriver) not a "comfusing programmable" type, DEVAR 332-AP with non clog Submersible Pressuer Transduser 5 PSI for year with out any proble, the 332-AP a alternating LEAD-LAG Duplex Pump cotroller with Digital RED LED readin feet and inch. Fot six years I just lost only two out of 126. For VFD pressure pomp control, I used Setra Pressure Transducer o-to-100 PSI, and for controller I used Fuji Electric PXG (PID) (1/16 DIN) and a 60 HP VFD. The VFD I prorammed for 30 % rump up and down for avoid any Water Hammer for stop and start tme. The system maintain 68 PSI for six years with out any problem, the I Retired. If You or anybody have any question, just look up Old Magyar information and You can call Me on the phone any time. Thanks.

Sir.

Just "Google" in DEVAR 332-AP and You can see the suggested Pumpcontrol on PDF and You can read the specification and the beauty of this control for Duplex lift station control simlesity.

Old Magyar.

Look at PIAXE with all its free downloadable software as a good place to start.

Arduino is expensive in comparison.....

Exceedingly cheap and still much faster than most applications need. You only need a PC or Laptop of almost any age to get started.

Its even possible to download the free software and get started EVEN BEFORE you buy the chips!!!

Click on here:-

http://www.rev-ed.co.uk/picaxe/