Most popular programable logic controller in the US?

J

Joerg

Guest
Hi Folks,

At c.a.e. I didn't get a lot or responses. Those of you who have dealt
with PLC units in industry: What is the most popular brand and type in
the US? Something that is cheap and practical.

Regards, Joerg

http://www.analogconsultants.com
 
Joerg <notthisjoergsch@removethispacbell.net> wrote:

Hi Folks,

At c.a.e. I didn't get a lot or responses. Those of you who have dealt
with PLC units in industry: What is the most popular brand and type in
the US? Something that is cheap and practical.
I don't know if the company or the product is any good, but, if I were in
the states and looking for a cheap practical range of PLCs that are easy to
buy I would try http://www.automationdirect.com
 
Joerg wrote:

Hi Folks,

At c.a.e. I didn't get a lot or responses. Those of you who have dealt
with PLC units in industry: What is the most popular brand and type in
the US? Something that is cheap and practical.
While not having worked with them, I got the impression that
the siemens Logo is trivially simple to operate and rather cheap.
They sell them for 120$ at overpriced distributors in quantities
of one here.

Rene
--
Ing.Buero R.Tschaggelar - http://www.ibrtses.com
& commercial newsgroups - http://www.talkto.net
 
On Fri, 29 Oct 2004 22:53:04 GMT, Joerg
<notthisjoergsch@removethispacbell.net> wrote:

Hi BFoelsch,

Depending on what you are trying to do a PLC can make life very easy. Most
people who go the PC route on automation designs do it because they are
comfortable with a programming language or technique, but they totally
underestimate the difficulty of managing real world I/O, which is very easy
with a PLC. Secondly, very few, if any, PC- based solutions that I have seen
permit on-line editing. There is a great deal to be said ( in the industrial
environment) for the ability to make program edits while the program is
running, and again, this is pretty much standard for PLCs and pretty much
unheard of with PCs. And of course, the PLC operating systems are rock-solid
compared to the Microsoft offering.


That is also what I have observed. There is another reason for a PC:
Everyone is familar with its file system and you can also write your
report right on it. No need to schlepp the laptop into a clean room
environment. Usually you can't take anything in there, or at least
shouldn't.

Online edit is possible though. We have done it when debugging
auto-bonders, laser cutters and so on. Single step, stop, manual head
movements to try something out, slow advance to see why a linear motor
didn't run smooth, it is all no big deal if the software can do that.
The OS was often non-Windows. There are some really good ones such as
QNX where latency times are very predictable. DOS, by the way, is also
rock solid and very frequently used in automation.

PLC would be even better but it does have to compete price wise. I am
pretty puzzled when I look at the distribution system. When I asked at
some local electricians places some didn't even know what PLC is. Others
said it can only be purchased through a 'few special outlets', whatever
they meant by that. One guy got so frustrated by the VAR runaround that
he bought his Moeller PLC unit through EBay.

Yes, the AB product is not the price leader, but it is the most popular,
most understood and most supported.


I assume they could do a lot more in sales if they were more available.
An example is our pellet stove. These have to run an auger, several
motors and must monitor 4-5 sensors. Low quantity products, the perfect
spot for a PLC unit. Yet they all go through the trouble of having their
own micro controller boards developed, something that just can't make
much sense in an industry where a few thousand units a year is a lot.

Regards, Joerg

http://www.analogconsultants.com
I've never used a PC based control system, but I understand they're
pretty slow and have high latency, a no-no in the industrial
environment. Until now we've been using AB SLC-500, but they're
getting too expensive so last week I set up a Siemens S-200 for a
trial of an app where the AB's are too slow. Hey, it's fantastic,
almost no latency and lightning fast response. The programming
environment (Step-7) is easy to use, instant switching between ladder
logic and symbolic language makes it a lot more readable depending on
if you're doing a bit of logic or some calculation. They're a lot
cheaper too.

The application in question is a hot melt spigot, it needs to start
the sequence in at most a ms from the input closure and run with a
resolution of a few ms to get the glue spots in the right place.

If you need it operator controllable/adjustable or generate reports
you'll need some sort of supervisory system communicating to it on a
PC. We use FIX/DMACS currently but it too is getting too expensive and
a bit behind the times.

Get your ass over to the Siemens website and do a read-up.

- YD.

--
Remove HAT if replying by mail.
 
Hi BFoelsch,

Depending on what you are trying to do a PLC can make life very easy. Most
people who go the PC route on automation designs do it because they are
comfortable with a programming language or technique, but they totally
underestimate the difficulty of managing real world I/O, which is very easy
with a PLC. Secondly, very few, if any, PC- based solutions that I have seen
permit on-line editing. There is a great deal to be said ( in the industrial
environment) for the ability to make program edits while the program is
running, and again, this is pretty much standard for PLCs and pretty much
unheard of with PCs. And of course, the PLC operating systems are rock-solid
compared to the Microsoft offering.


That is also what I have observed. There is another reason for a PC:
Everyone is familar with its file system and you can also write your
report right on it. No need to schlepp the laptop into a clean room
environment. Usually you can't take anything in there, or at least
shouldn't.

Online edit is possible though. We have done it when debugging
auto-bonders, laser cutters and so on. Single step, stop, manual head
movements to try something out, slow advance to see why a linear motor
didn't run smooth, it is all no big deal if the software can do that.
The OS was often non-Windows. There are some really good ones such as
QNX where latency times are very predictable. DOS, by the way, is also
rock solid and very frequently used in automation.

PLC would be even better but it does have to compete price wise. I am
pretty puzzled when I look at the distribution system. When I asked at
some local electricians places some didn't even know what PLC is. Others
said it can only be purchased through a 'few special outlets', whatever
they meant by that. One guy got so frustrated by the VAR runaround that
he bought his Moeller PLC unit through EBay.

Yes, the AB product is not the price leader, but it is the most popular,
most understood and most supported.


I assume they could do a lot more in sales if they were more available.
An example is our pellet stove. These have to run an auger, several
motors and must monitor 4-5 sensors. Low quantity products, the perfect
spot for a PLC unit. Yet they all go through the trouble of having their
own micro controller boards developed, something that just can't make
much sense in an industry where a few thousand units a year is a lot.

Regards, Joerg

http://www.analogconsultants.com
 
"Joerg" <notthisjoergsch@removethispacbell.net> schreef in bericht
news:uYUgd.2722$zx1.1794@newssvr13.news.prodigy.com...
Hi Frank,

Farnell has them:

http://uk.farnell.com/jsp/endecaSearch/searchPage2.jsp?x=17&Ntt=siemens+log
o&Nty=1&N=401&Ntk=gensearch&y=10

Which means you should be able to order them through Newark too.
Price is ~88 uk pounds. The cheaper ones (77 pounds) don't have a
display and can only be programmed via PC and software.


It seems to be easier to buy PLC units in Europe. I checked Newark and
Digikey for the Logo. Zilch.
Yes, it is strange you can't get them. The Siemens logo is not on
Newarks' website, but I thought they should be able to sell you items
from the Farnell catalog.

For quick solutions there's also the stuff from Zworld, but these are
programmed in C and cost a lot more.

That is great but I don't want to get involved with a technology when
EBay is the only practical way to buy stuff.
Well, you only have 1 swimming pool I guess. Or did you need
more?

--
Thanks, Frank.
(remove 'x' and 'invalid' when replying by email)
 
On Sat, 30 Oct 2004 22:54:18 GMT, Joerg
<notthisjoergsch@removethispacbell.net> wrote:

Hi Frank,

Farnell has them:
http://uk.farnell.com/jsp/endecaSearch/searchPage2.jsp?x=17&Ntt=siemens+logo&Nty=1&N=401&Ntk=gensearch&y=10

Which means you should be able to order them through Newark too.
Price is ~88 uk pounds. The cheaper ones (77 pounds) don't have a
display and can only be programmed via PC and software.


It seems to be easier to buy PLC units in Europe. I checked Newark and
Digikey for the Logo. Zilch.
Strange, here we just call a representative and they'll skip, hop and
jump over with a catalogue. And we're half-way out in the boondocks.

Siemens even loaned us a LOGO and an S-200 for testing, complete with
cable and proramming software. They won't regret it, we'll need 5
basic S-200s and one with a rather large amount of expansion modules.

The total amount spent will be just about the cost of a basic SLC-500,
go figure.

- YD.
--
Remove HAT if replying by mail.
 
On Tue, 02 Nov 2004 18:45:05 GMT, Joerg
<notthisjoergsch@removethispacbell.net> wrote:

Hi YD,
The total amount spent will be just about the cost of a basic SLC-500,
go figure.


How much did these five basic ones cost you per unit?
Not me doing the buying, and I can't recall of the bat, but I believe
R$2000 was mentioned. At the current exchange rate that's about
US$600. Much of that is due to taxation at an incredible rate.

- YD.

--
Remove HAT if replying by mail.
 
Hi YD,

How much did these five basic ones cost you per unit?



Not me doing the buying, and I can't recall of the bat, but I believe
R$2000 was mentioned. At the current exchange rate that's about
US$600. Much of that is due to taxation at an incredible rate.


$600 per unit? Ouch. You guys must really pay outrageous taxes because
at that price you can install a leather-seat and marble PC solution. At
least in the US.

Regards, Joerg

http://www.analogconsultants.com
 
Joerg wrote:
Hi Folks,

At c.a.e. I didn't get a lot or responses. Those of you who have dealt
with PLC units in industry: What is the most popular brand and type in
the US? Something that is cheap and practical.

Regards, Joerg

http://www.analogconsultants.com
Anybody here have experience with Toshiba's line of PLCs?

--
Paul Hovnanian mailto:paul@Hovnanian.com
------------------------------------------------------------------
I think you left the stove on.
 
On Wed, 03 Nov 2004 21:56:05 GMT, Joerg
<notthisjoergsch@removethispacbell.net> wrote:

Hi YD,

I checked today and that's about the cost of it. Besides import taxes
and stuff I guess there's quite a bit of markup on it too. Hell,
around here they'll nick you USD200 for a beat-up 15 MHz scope.


Which country is that? First I thought South Africa but the exchange
rate doesn't match so now I am puzzled.

Anyway, if stuff is so much more expensive than elsewhere how can you
guys compete in exports?
Brazil, coincidentally I happen to live close to Chaos Master. Not
everything is expensive, mostly imports, if there's a "national
similar" there's a heavy surcharge. Which in this case would be the
ALTUS PLCs of which we happen to have quite a number. We're gradually
replacing them as they're pure crap, ten years behind their time,
taking advantage of the situation by charging triple of what they're
worth.

Exports are doing fine, mostly raw materials, agricultural produce,
and some manufactures. The current exchange rates make them attractive
so the trade balance is in our favor. Overall the economy at the
moment is at an upward turn.

- YD.

--
Remove HAT if replying by mail.
 
Hi Rene,

While not having worked with them, I got the impression that
the siemens Logo is trivially simple to operate and rather cheap.
They sell them for 120$ at overpriced distributors in quantities
of one here.
Over here it's worse. Tried Google and other searches but no place to
find where they have a price list. Before I evaluate any options I
always want the cost first, to see if it makes sense at all.

Then last week I tried it through the Siemens site. Keyed in all the
info they wanted, plus a question where to buy LOGO and other stuff. No
answer. That's not a good thing.

Regards, Joerg

http://www.analogconsultants.com
 
Hi Spehro,

Brazil's Embraer is giving Bombardier a run for their money in the
regional jet business. Aerospace is a good tech business.


Yes. I have only seen Embraer turboprops close up but these were very
solid planes. If they build jets the same way they will soon be a
dominant figure in the marketplace. But I still like my fancy Bombardier
pen eventhough it was confiscated by my wife.

Regards, Joerg

http://www.analogconsultants.com
 
Hi Jim,

Reminds me of a funny situation in our family... Hispanic son-in-law
can't speak Spanish, because his immigrant parents thought being
American meant speaking English (somewhat different from today, eh?).


Sometimes it was less funny than that. A neighbor told me that they were
kind of forced not to speak Spanish at school. So now he can't speak it
much anymore. I am against bilingual education the way our public
schools propose it, not just because the US has chosen English as the
official language many moons ago. But also for the sake of immigrant
kids since that quickly makes them 2nd class in business because they
may not master technical English well enough.

But my oldest son, the programmer, speaks Spanish (Mexican-style) and
Portuguese, both learned from the street, Spanish from working laying
sprinkler systems in Tucson while attending U of A, Portuguese then
rapidly learned from multiple business trips to brazil.


I hope he keeps it up by socializing with native speakers. Otherwise
these skills vanish over the years. This happened to me with Dutch.
Funny thing is, after a few beers it's all back. Well, maybe not anymore
because five years have passed since that trip.

It can also work the other way around. I grew up speaking German. A few
months back we had visitors from there and the second night they asked
me to say our evening prayer in German so they could understand. Errr,
ahhhm, ahem, well.... boy has that become rocky.

Regards, Joerg

http://www.analogconsultants.com
 
On Thu, 04 Nov 2004 18:37:02 GMT, the renowned Joerg
<notthisjoergsch@removethispacbell.net> wrote:

Yes, it is pretty remarkable how Brazil is doing today. It is important
though to add some high-tech into the mix because raw materials and
agriculture won't let you get beyond a certain level. Unless someone
finds gold or lots of oil, of course.
Brazil's Embraer is giving Bombardier a run for their money in the
regional jet business. Aerospace is a good tech business.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
 
On Fri, 29 Oct 2004 20:29:38 GMT, the renowned Joerg
<notthisjoergsch@removethispacbell.net> wrote:

Hi Folks,

At c.a.e. I didn't get a lot or responses. Those of you who have dealt
with PLC units in industry: What is the most popular brand and type in
the US? Something that is cheap and practical.

Regards, Joerg
Joerg, sci.engr.control is the place to ask. AB is the safe choice of
big industry. I think it depends a lot on whether you need a micro-PLC
that just has to be cheap, or whether you want something that the
plant people can program and so on. There's one or two orders of
magnitude variation in price, and somewhat less in capability.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
 
Hello YD,

Brazil, coincidentally I happen to live close to Chaos Master. Not
everything is expensive, mostly imports, if there's a "national
similar" there's a heavy surcharge. Which in this case would be the
ALTUS PLCs of which we happen to have quite a number. We're gradually
replacing them as they're pure crap, ten years behind their time,
taking advantage of the situation by charging triple of what they're
worth.


Those are signs of hardcore protectionism, something that has never
worked anywhere in the long run. It causes the inflationary effects you
mentioned and puts a damper on innovation.

Exports are doing fine, mostly raw materials, agricultural produce,
and some manufactures. The current exchange rates make them attractive
so the trade balance is in our favor. Overall the economy at the
moment is at an upward turn.


Yes, it is pretty remarkable how Brazil is doing today. It is important
though to add some high-tech into the mix because raw materials and
agriculture won't let you get beyond a certain level. Unless someone
finds gold or lots of oil, of course.

Many years ago I had an oscillator made in Brazil. It was interesting,
every time someone was in my lab and had to use it they stared at the
front panel. All in Portuguese. So I placed a cheat sheet underneath.

Regards, Joerg

http://www.analogconsultants.com
 

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