HELP A BIGiNNER: What is the Unitary plc, Modular plc and Rack-Mounted

[RACE_NOISE]

Hi, can i please get some help with these types of plc's
what is the Unitary plc, Modular plc and Rack-Mounted plc?
and also if possible can you discribe the main criteria for each of these types which must be considered when selecting a controller to fit a particaler app? so like costs versatility and scanning.
thank you

 

[Steve Bailey]

http://www.freestudy.co.uk/

 

[RACE_NOISE]

Hi Steve, thanks for replying, iam havin a look at this link and i found some good things in it. thank you

 

[silva.foxx]

Race Noise... welcome to the forum. One thing you need to get used to with this site, and as a student, is to show initiative in your research. We've all been there. You are opening yourself up to "lazy pupil wanting homework answers" label. I look back at my earliest posts to this forum and cringe!

This same question has been raised here in the past. Use the search function up top or Google it. Good luck in your search.

http://www.plctalk.net/qanda/search.php?searchid=1585769 38 results!

 

[STL???]

First assignment from the ONC/HNC PLC unit by any chance

 

[rdrast]

This question is useless.
The course is obviously useless.
Posting in forums for the answer is equally useless.

 

[ghettofreeryder]

I agree. Does this course mean anything in the real world?

 

[jvdcande]

I agree. Does this course mean anything in the real world?

Maybe. But the question about unitary, brick etc doesn't. It's typically a question stated by a lecturer who doesn't know the beginning of PLCs. If he/she would have any experience, he/she would certainly not ask the pupils such a useless question.

RACE_NOISE, it might be a good idea to direct your lecturer here. He/she might learn a thingy or two (or more).

Kind regards,

 

[leitmotif]

The question may be appropriate for the first lecture. PLCs do come in different sizes and it is important to understand this and more important to understand with bigger size comes more complexity and capability and price.

The other value for the student himself gained from asking us this "dumb question" is not only does he make contact with real world but he is better able to quantify the value of information he is getting in the course.

Dan Bentler

 

[demmons]

Very true, Dan, I once had an internal combustion engine professor go on a rant about how turbochargers were useless. Having driven tractor trailers, I would say the folks at Kenworth, Mack and Peterbilt would tend to disagree...

 

[TimothyMoulder]

Okay, let's settle this once and for all:

Unitary - A PLC developed after the declaration of the United Kingdom by the British. It is sometimes called a "brick" because angry Irishmen would throw them at the yeomen's windows as an act of protest.

Modular - Any PLC developed by Modicon. These caught on in a big way with the California surfer crowd, who use them to produce high-quality balsawood boards, giving rise to the expression, "Dude, that tokin' board is totally modular".

Rack-mounted - a PLC designed to be worn in a manner similiar to a brassiere. Their utility was dubious, but nevertheless they were wildly successful in industry through the early part of the 20th century, until the 60's, when trying to work on one would get you sued.

Best of luck on your finals.

TM

 

[Steve Bailey]

Timothy,

The question has already been settled "once and for all".

http://www.plcs.net/dcforum/DCForumID4/359.html

 

[OkiePC]

Wow, it's already October and this the first time I noticed this common "back to school" question.

BTW, I think the people who prepare the curriculum are actually more lazy than the students from some of the antiquated and useless questions they provide.

 

[Steve Bailey]

It's part of a standardized British curriculum. It first showed up here on PLCtalk.net almost a decade ago and we've been making snarky comments about it ever since.

 

[TimothyMoulder]

ROFL! Heh, Tom's a character I do like my definition of "rack-mounted" better tho'