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A recent poll by Control magazine shows that only 12% of users report using primarily digital buses. Keith Larson mentioned the report in the article, “Industrial Networking: The Next 20 Years”: “…a just-completed survey of Control readers indicated that a full 54% of survey respondents still use mostly 4-20mA analog hardwiring for instrument communications. Only 12% reported using primarily digital buses.”
I wish I knew if they were talking about their existing infrastructure or new projects. If new projects, then I am really baffled. Fieldbuses have been around long enough (PROFIBUS started over 20 years ago) and are widespread enough (over 24,000,000 PROFIBUS nodes installed so far) that this should be an easy decision. Is it that there are too many choices? Well, in North America there are really only two choices in each category:
Discrete: PROFIBUS DP or DeviceNet
Process: PROFIBUS PA or Foundation Fieldbus
Industrial Ethernet: PROFINET or Ethernet/IP
PROFIBUS DP and PROFIBUS PA have different physical layers, but use the same protocol. PROFINET easily integrates with PROFIBUS and other networks, too, including DeviceNet and FF. To me the choice of all PROFI looks easy, but I may be ever so slightly biased. So don’t take my word for it – try both choices. Pick a couple small projects, educate yourself about both alternatives, then implement both. This requires some time commitment, but it’s better than staying stuck in the past. I’m pretty confident which technology will win the comparison.
“If you do what you’ve always done, you’ll get what you’ve always gotten.” If your facility will not benefit from easier installation, faster commissioning, quicker troubleshooting, and more uptime then by all means keep use hard wiring. If it will, then get on a bus!
Looking at very different scary numbers, there was a really interesting/scary article in Computer magazine: “The $100,000 Keying Error” By Kai A. Olsen. It’s all about what can happen when your manually entered numbers are un-checked. Think HMI instead of banking and it applies to our automation world, too.
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Sitting in another airport (Houston Bush) waiting for a plane delayed by weather, here’s my report from ABB Automation World:
Many of the industrial automation bloggers were here in Houston and they blogged about the conference. You can find posts from Greg Hale, Walt Boyes, and Gary Mintchell. Plus news items from others. They provide a good overview of the overall conference, but my interest is much narrower. So, I’ll focus here on the PROFIBUS and PROFINET news from ABB.
PROFIBUS is prominently featured in ABB’s architecture. I attended several of the workshops presented by ABB personnel. They give equal opportunity to PROFIBUS PA and Foundation Fieldbus for process instruments, working with the customer to help them determine the best choice. In the comparison workshop they gave what I felt was a fair comparison between HART, FF, and PROFIBUS. Their recommendations follow the lines you would expect: when the user wants “control in the field” they’ll go FF; when they have a large amount of discrete IO they’ll go PROFIBUS. For discrete IO, PROFIBUS DP is clearly their first choice. ABB goes to great lengths to certify third party devices to work with their systems. In the process they provide a lot of value-add like documentation, GSD files, and more. Over 350 PROFIBUS devices are thus provided for, more than for FF or HART.
Speaking of HART, I sat in on Ed Ladd’s workshop on WirelessHART. Recall that PI and FF are cooperating with HART Communication Foundation (HCF) on a common gateway approach to wireless process instruments. Score one for the users. To think we almost did our own wireless process instrument spec. Be thankful for the “almost.” Speaking of wireless spec proliferation, I ran into Walt Boyes and he shared some of the tribulations with the ISA 100 effort. Watch his blog for the latest on that topic.
ABB has an integration initiative that highlights the power of PROFINET. (Well, it highlighted PROFINET to me, anyway.) The initiative creates a common Industrial Ethernet architecture ranging from electrical substation equipment to process instruments with drives and discrete IO in between. The Industrial Ethernet architecture includes FF HSE, a substation protocol, and PROFINET. All coexist on a single network. (That’s the beauty of Ethernet – on the wire many protocols can coexist – think web browsers, file downloads, and emails as a simplistic example.) PROFINET covered the largest application area and its ability to use proxies to integrate other networks was relied upon. ABB has already introduced drives with PROFINET IO connectivity, too.
I rate a conference based on the number of times they say one of my favorite “P” words (PROFIBUS or PROFINET). This conference rates highly – even the WirelessHART presentation added to the count.
Speaking of the word PROFINET, Phoenix Contact did some video reporting from Hanover Fair. They used the right word, too.
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The final numbers for Hanover Fair are just in – in time for this, my final Hanover Fair post:
5,100 exhibitors from 60 countries
200,000 visitors
3,200,000 leads generated (a 15% – 20% increase)
This blogging software won’t let me post videos, so click here to get the sights, sounds, and feelings of the fair.
Speaking of feelings, yesterday we tied a record low in Phoenix. The humidity dropped to 2% - when we say it’s a dry heat, we really mean it. I know not to expect low humidity in Houston! If you’ll be at the ABB Automation World, look me up.
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Now I’m at the airport with time for my next to the last observation from Hanover: I spent some time with PROFIsafe expert Wolfgang Stripf in front of the PROFIsafe display. Here’s the display:
It depicts an automotive example but applies to any dynamically changing process. The demo highlights safety functions in drives, dynamically reconfiguring a laser scanner, and integrating AS-I emergency stop buttons. Incidentally, the red square is a new type of camera-based “light curtain.” If you look closely at it you can see a little guy in a hard hat sitting on top. When you place him on the moving car, the laser scanner recognizes that more than the car is passing through and executes a safety stop. (The laser scanner is the yellow and black box at the top of the panel.) The new drive safety functions show the different options for creating a safe situation. It used to be that your only choice was to remove power, but now you also have the ability to go to a safe speed, a safe position, and more. The emergency stop buttons across the bottom are on the AS-I bus but are brought into the safety system. It’s hard to see in the photo but some of the devices are PROFIBUS devices and some are PROFINET.
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Monday morning and I’m about to leave for the airport en route to Houston for the ABB Automation World. I’ll be speaking about PROFIBUS and PROFINET on Thursday. But before I go let me share some of the discoveries I made at Hanover Fair.
Phoenix Contact showed managed Ethernet switches that have their configuration saved in a plug-in to simplify replacement. If you have to replace the switch, just move the plug-in to the replacement switch and all the configuration is done; no need to connect to it and configure it. The switches also look like IO Devices to PROFINET or Ethernet/IP (the one they look like is saved with the other configuration data). As an added bonus, the switches support the PROFINET Media Redundancy Protocol (MRP). They also showed a new PROFINET-based PLC.
Speaking of PROFINET-based PLCs, Omron was showing a new PLC to be released in July. It is PROFINET-based and includes PROFINET MRP built in. They are offering switches that support MRP, too. One important measure of the success of a fieldbus network is the number of controller manufacturers that support it. This makes four manufacturers that offer (or have announced) controllers that use PROFINET: Siemens, Phoenix Contact, GE Fanuc, and Omron. How many of the other Industrial Ethernets are supported by more than one controller? Are any?
NEC has long offered an ASIC for PROFINET that includes PROFINET IRT functionality. In the PI booth they also showed an IO-Link chip.
I discovered a couple Industrial Ethernet Tools to ease troubleshooting of PROFINET networks. ANF Data Systems will release their tool, PronetA, in a few months. Hilscher has already released their Net Analyzer that collects statistical information about the network and integrates Wireshark so you can “look inside” the Ethernet frames.
One other bit of PI news: our long-time PROFINET colleague, Joerg Freitag was officially elected chairman of PNO (the PTO-equivalent organization in Germany).
PI did not have all the news; there were a few other items from other consortiums. ODVA announced that they are now solely responsible for Ethernet/IP. Apparently ControlNet International shared the marketing responsibility before. Who knew?
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The final new press release from the PI press conference covered new white papers. [From O’Hare airport in Chicago, between flights.]
The news: PI publishes two new strategy documents
The gist, part 2: The second one is “Enhancing the High Performance of PROFINET.” It builds on the paper presented at the 12th IEEE Conference on Emerging Technologies and Factory Automation: “Limits of Increasing the Performance of Industrial Ethernet Protocols” that I posted about here <link> after the SPS/IPC/Drives show last November. Since the IEEE paper itself is not generally available, this white paper provides an overview of the findings and a report on enhancements to PROFINET’s speed that are ongoing.
The significance: Although PROFINET is faster than EtherCAT in all but the smallest systems, we accepted this as a challenge. The ongoing project is to make PROFINET the fastest in even the smaller systems. Details of this project were visible in the booths of several of the project participants that I visited and in the PI booth. Preliminary reports show that we will be faster while of course remaining backward compatible. This is one of those situations where competing technologies spurred developments to make an even better Industrial Ethernet.
The gist, part 1: The first paper mentioned in the press release at first blush seems to be more of an internal look than something of general interest. However, “Strategic Overview: PROFIBUS + PROFINET” is really essential to everyone’s understanding of the relationship between PROFIBUS and PROFINET – the work well together. In fact, they were designed to work together.
The significance: I am proud of the fact that we did not just wrap a PROFIBUS datagram in TCP/IP and call it our Industrial Ethernet. The PROFIBUS and PROFINET protocols are different; how else could we take advantage of all the benefits that Ethernet offers and also create new industrial uses like our easy peer-to-peer integration? But because we designed them to work together and share a common set of application profiles, we get the best of both worlds. This is why our safety profile (PROFIsafe) can seamlessly work on both PROFIBUS and PROFINET. The application stories alone make this worth a read.
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The big news related to PROFIBUS and PROFINET (and maybe for the show over all) was the continuing growth of the PROFIBUS and PROFINET fieldbuses. What the numbers were and meant were in an earlier post. The other topics from the PI press conference included:
The news: IO-Link Integration into PROFIBUS and PROFINET
The gist: IO-Link is a fieldbus-independent connectivity method for intelligent sensors. It is designed to bridge the last meter between an IO block and the device while using conventional wiring for the sensor but superimposing a digital communications means over the conventional wiring. This allows configuration and diagnostics actions to be initiated remotely from an engineering station instead of with a handheld tool at the sensor.
The significance: Sensor makers are rapidly adopting this technology and many products were shown in the sensor manufacturers’ booths. PROFIBUS and PROFINET are the first fieldbuses to have connectivity to IO-Link and many brands of IO blocks (IO-Link masters) were shown with PROFIBUS or PROFINET connectivity. MESCO offers an IO-Link toolkit and Hilscher offers a netX-chip-based reference design for the masters. I introduced you to IO-Link a couple years ago and it had been interesting watching it mature. Judging from what I saw in Hanover, its time is now.
The news: International Cooperation
The gist: PI has been engaged with other, competing organizations to unify supporting technologies to the benefit of the end user. The EDDL Cooperation Team (ECT) dates back some years and last year added the initiative to create a successor to EDDL and FDT that satisfies requirements for both. This leaves the device manufacturers with only one standard to support and the user with only one technology to learn. The ECT consists of PI, Fieldbus Foundation (FF), HART Communication Foundation (HCF), OPC Foundation, and the FDT Group. A more recent cooperative team is the Wireless Cooperation Team (WCT). It is actively working toward unified approaches to wireless process devices. The WCT includes PI, FF, and HCF.
The significance: Not all technology consortiums are as forward thinking as PI in recognizing the importance of simplifying the life of the end user. A user should ask: “Can I safely choose a fieldbus whose organization is not participating is such a cooperative effort?”
Now I’m off to the airport for the long flight home. More news will follow after I land.
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The leading news at the PI press conference covered the continuing growth of PROFIBUS and our first node count of PROFINET devices. (You can read the full press release here.) I tend to get all excited about PROFINET at the expense of PROFIBUS, so before I get to the PROFINET story, here’s the scoop about PROFIBUS. In calendar 2007, we sold 4,500,000 devices – a 25% increase over the year before. This brings our total installed base through ’07 to 23,300,000. To put this in perspective: we probably sold more PROFIBUS last year, than any other fieldbus in its lifetime (except for Interbus). [And, no we don’t count HART because it’s not a bus. But just so you know – they claim 23,000,000 installed devices with only about 10% actually using the HART functionality; the rest just use 4-20 mA for the process variable.] For a little more perspective, we probably sold more PROFIBUS last year than all the Industrial Ethernets over their lifetimes… combined. Ouch.
How do we know how many PROFIBUS devices were sold? Almost every device has a chip. The chips are made in a handful of different chip foundries. We count the chips. We are therefore very confident in the accuracy of the number.
Although I get all excited about the numbers and the fact that we’re number one in market share by a long way, so what? What if I’m a user or prospective user of a fieldbus? Why does this matter to me? It shows that PROFIBUS is a really well-accepted technology; I can safely choose to use it, too. Knowing of this large volume of devices installed I can correctly surmise that there are lots of products, lots of installations, lots of tools, and lots of know-how available.
For all of us who predicted that Industrial Ethernet would usurp the traditional fieldbuses – I guess we were wrong about the timetable.
The number of PROFINET nodes through 2007 was (ta-da)… 1,140,000. This is a pretty impressive number considering we got a later start than the other Industrial Ethernets. But I think even more impressive is what we counted and how we counted them. It would be tempting to count the infrastructure components, like Ethernet switches. We resisted temptation. It would be tempting to make an estimate of the number of devices. We resisted this temptation, too.
We counted only controllers (PLCs), remote IO stations, HMIs, robots, proxies, drives, and sensors. Note that we did not count each IO module, just the IO station. Some Ethernet switches include PROFINET IO capability so you can make them part of your engineering system for diagnostic and alarm purposes. We did not count these switches either.
How did we count the nodes? This is a lot harder than counting PROFIBUS nodes because PROFINET uses just standard Ethernet – no chip is required. So we engaged an independent third party to count anonymously (the third party is called a “notary” in the press release). We told the notary which companies to contact. The notary contacted them and requested their PROFINET node count. The companies returned their count directly to the notary. The notary then gave us the total. We never saw the individual companies’ numbers, just the total: 1,140,000.
One of the questions at the press conference was: “How do the other Industrial Ethernets count their nodes and what do they count?” “You’ll have to ask them.”
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I’m finally able to sit down and blog about this year’s Hanover Fair (starting on the train from Hanover to Frankfurt). The sitting part feels really, really good after four very full days at the fair plus evening meetings. Over the next several posts, I’ll tell you (and show you) what I saw. I’ll start with a little about the fair itself. In upcoming posts I’ll fill you in on the PI press conference, some details of what was in the PI booth, new products discovered, and my general impression of the fair. I might even offer an opinion or two about the fair and the news emanating there from.
Hanover Fair (officially Hannover Messe) runs for five days, April 21 – 25. It encompasses multiple shows including Industrial Automation. The fairgrounds has 27 halls and the industrial automation show filled 9 of them.
Our booth consisted of a display area of 330 square meters (3,500 sq ft) plus a theater presentation area of 120 m2 (1,300 sq ft) and the Automation Lounge of 90 m2 (1,000 sq ft). The theater and lounge were shared with the Interbus Club. [Wait a minute, you’re thinking - doesn’t Interbus compete with PROFIBUS? Yes, but the Interbus folks decided to not create their own Industrial Ethernet version of Interbus, but to adopt PROFINET as their Industrial Ethernet implementation instead. So, now we’re friends.] Oh, and if you’re wondering what an Automation Lounge is, I blogged about that from last year’s show.
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Overlooking the Booth
In the display area
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Presentation in progress
Our display area featured a PROFIBUS wall, an IO-link wall, a TCI wall, a PROFIsafe wall, and a PROFINET performance wall. The floor space was filled with displays from member companies. Sixty nine members participated in the show. In the presentation area was a large PROFINET wall. This wall featured 109 products from 19 companies.
Hanover Fair may be held in Germany, but it is very much an international show. More than 30% of the visitors are international visitors, mostly from the Americas. This is in contrast to the three-day November SPS/IPC/Drives Show in Nuremberg which draws a primarily German and European crowd. I was able to visit with quite a few US-based PTO members during the week. And as a pleasant surprise I ran into s few friends from my Wonder years. How international is the show? I even visited the booth of Akron, Ohio, home of my alma mater.
My general impression was that the fair was not quite as well attended as last year. (Of course I only visited 3 of the halls, so we’ll wait for the final numbers from the show organizer.) This year though, PROFINET was absolutely pervasive. Even companies that you associate with other protocols showed comprehensive PROFINET offerings. Secondarily, IO-Link has matured into a widely-adopted standard with products and tools in many booths, especially the sensor makers.
Next time: the big news from the show.
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Where are the automation professionals of tomorrow? Today, many of them are in Atlanta competing in the FIRST Robotics Competition. I know because my oldest grandson is there competing. They just finished a match. The first 15 seconds is all automated. His team scored 4 points in that part, which is good because he did all the programming… in C. And he’s still a freshman in high school. Cool thing number one: I can IM with his father in MA from here in AZ as we (cool thing number two) watch the web video feed live. (A high school freshman is not too young to learn about PROFIBUS and PROFINET, right?)
UPDATE: My grandson's team finished second! The team's story was in their local paper.
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Hanover, Houston, and Raleigh? Is this a blog or a travelogue? Maybe both. It’s certainly travel season in my world now. In the last month, I’ve been to Portland (OR), Montreal, Toronto, and Cleveland. I’m headed for Hanover, Germany, this weekend for the Hanover Fair. I’ll be hanging out at the PI booth all next week (Hall 11, Booth A41). Stop by and say hello if you are going to be there. If you can’t be there, no worries - I’ll blog when I can about the sights and announcements at the Fair. I’ll slip out of the booth on Wednesday morning to participate in the Molex panel discussion on Industrial Ethernet.
As soon as I get home I’ll leave again - this time for Houston and ABB Automation World where I have a speaking slot on Thursday about PROFIBUS and PROFINET.
Then a break until May 15 in Raleigh for the PROFINET one-day training event there. Meanwhile Mike A is off to Boston, Milwaukee, Calgary, AB, Richmond, VA, and Anchorage, AK. Yes, it’s definitely travel season here… and just when the weather in Scottsdale was getting comfortable (97 today).
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It’s hard to keep up with blog-able news when your laptop battery dies. Finding a power outlet in an airport is not easy… and that’s the only place I’ve had “spare” time lately. Thanks to those of you who noted my absence and “gently chided” me to get busy. Anyway, here’s some news from the road…
Montreal. It didn’t snow while we were there, but the snow had drifted outside the hotel ballroom window taller than a person. This was the second time we had used this year’s material. Course feedback was generally positive with some folks asking for more details in one area or another while other folks asked for just the opposite. The one constant was for more demos. We don’t often get emails from attendees after PROFINET events (except for the occasional question), but here’s an excerpt from one we got from Montreal: “Thank you for the training, it was really interesting. I was with those who thought that you couldn't achieve determinism and Real Time with Ethernet. But you convinced me. … thanks for the nice training. It is one of the best I've seen so far (good service, good information, good food, good sense of humor, good entertainment, good knowledge and free...what else can we ask for).”
Toronto. Well, Burlington really. In the small world department, I used to work in Burlington. If fact, I had a chance to visit my former colleagues at Avantis. Back to the class itself, we had a lot of positive feedback from the attendees here; typical: “Great day, educational and enjoyable.” We always have one or two requests for “hands-on” time. It’s just not possible with the size of these events. Our compromise in this area is to do the demos.
Cleveland. (More of a homecoming for me since I was born and raised in northeastern Ohio. I should have snuck out to the Indians game Wednesday night but I didn’t bring my long-johns.) A couple negative things from Cleveland – the room was too warm and the presentations jump around a bit. We’ll fix the latter before Raleigh and as far as the former goes, I’ll have to remember I’m not in Scottsdale. On the positive side: “Nice job! Well organized, prompt! I was able to gain the amount of information and exposure I was looking for in a single day event!” I always give the sponsors/exhibitors a Course Evaluation form as well. One of them identified themselves as a sponsor and commented: “I am very impressed with your program. From setup to attendance to content – fantastic job!”
Las Vegas and Houston. Mike A was in Las Vegas for the PROFIBUS one-day training event and with Mike B in Houston for the PROFIBUS in Process training class.
I feel like I’m tooting our own horn a lot here, but we deserve it (he says humbly). Seriously, come to one and judge for yourself. You will learn a lot.
I’m back in the office today. My daily Dilbert calendar was still on March 18 when I got here. Although I did run through the office twice since then to pick up stuff I needed for the training classes. After the cold weather of Montreal, Toronto, and Cleveland, today’s high of 84 in Scottsdale is welcome. Not that I’ll be out in it.
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…it’s Wednesday night. <insert pratfall here> On second thought, there’s no need for the pratfall. We’ve had a good couple days here in Oregon. [If you missed the obscure SNL reference, click here.]
The PROFINET one-day training event on Tuesday went very well especially considering that it was the first of the year. We’ll have to do some editing to get the times down a bit, but the attendees were very engaged right through the end. There were a lot of good questions along the way, too.
What did the attendees think of the class? Here’s a sampling of comments from the Course Evaluation forms:
“The course was very informative, engaging, and educational.”
“I was very impressed at how knowledgeable the presenters were. They were able to clearly answer some very esoteric questions.”
On the constructive criticism side: even though we beefed up the security section this year a couple people asked for even more. And we had as many people say that the course was too short as too long; most said the length was just right.
One comment deserves an answer: “The class is a good overview, but really to cover the information in enough depth to make it usable would take weeks.” I guess it could take weeks if you were implementing every facet of PROFINET. But that’s true of any comprehensive technology. The beauty of PROFINET is that you just need to learn and implement the facet you need. There is no need to learn all about motion control if all you need is IO. The important thing is that you can start with just IO and then when you need to add motion control you build on the knowledge you’ve already accumulated. You don’t have to start over learning a new technology, new tools, etc. We recognize that the best we can hope to provide in one day is an overview. Having an overview you can decide to adopt the technology. Then there are more in-depth classes available like our own PROFINET Certified Network Engineer class as well as vendor classes on their tools.
I was glad to see one comment about the “nice touch of humor occasionally.” But was surprised they cited Karsten’s humor and not mine. <sigh>
At the PROFINET Developer Workshop today I was surprised by the number of motion control folks we had. I know we helped a number of companies on their way to adding PROFINET to their products.
We’re off to a roaring start with PROFINET; Process starts next week in Houston and PROFIBUS in Las Vegas. We take PROFINET to Montreal, Toronto, and Cleveland after that.
[Posted Thursday since my flight home was delayed. Ah, the joys of business travel.]
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“One in-depth study conducted by a group … with a combined exposure of over 50 billion hours, concluded that production increased as safety increased,” reports Charles M. Fialkowski in “Safety Instrumented System design is all about the process.”
Although this is somehow counterintuitive, better safety equals better production. We’ve been preaching this for years. We even offer a white paper from ARC on our website, “PROFIsafe: Networked Safety for Process and Factory Automation,” that reinforces that point.
Charles’ article provides the best overview I’ve seen of the process of implementing safety. Definitely something you should read. (I actually just recommended an article that doesn’t have my favorite P-word in it! So, just so you know – you can implement safety over a bus now, like PROFIsafe over PROFIBUS and/or PROFINET, wired and/or wireless.)
Next week I’ll be singing “On the road again…” as I’m headed to Portland, OR for our first PROFINET one-day training event of the year. We’ve revamped the class this year, so even if you’ve attended before, there are new things to see and learn this year. Also in Portland we’re holding our first PROFINET Developer Workshop of the year. (I’ll have a special prize for the first person at either event to tell me they read this blog post.) More about the training class here and the workshop here. I hope to see you in Portland… or Montreal… or Toronto… or Cleveland… or…
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“Yellow is the new Green.” In order to avoid confusing this observation with pronouncements to Curious George’s friend in the yellow hat, I might add “Purple is the new Green.” In fact, “Green is the new Green.” (Or, more accurately “PROFINET Green is the new Green.”) Yellow represents AS-I; purple, PROFIBUS; and green, PROFINET. And Green means good for the environment.
In what way are fieldbuses environmentally friendly?
At the AS-interface seminar in Richmond yesterday, presenter Helge Hornis showed a graph of copper prices increasing dramatically over the last several years; tripling in price. (Copper theft is a major problem in Arizona where thieves rip copper pipes and wiring from houses under construction. They even rip copper wires from freeway light posts. A new state law requires positive identification of the survivors who try to sell the copper to recycling centers.) He mentioned in passing that cable jackets are based on petrochemicals (plastics). Back to Helge’s point: the cost of wire is going up, use AS-I to keep the cost down. Use one bus cable instead of many individual wires to individual devices.
All of this prompted me to think about fieldbuses in general as an environmentally friendly approach to business. Here is my quick list of green benefits of fieldbuses:
Less wire. Less copper used means less mining and refining. Less plastic means less drilling and refining, not to mention less dependence on foreign oil.
Less conduit. Fewer wires mean fewer conduits. Steel conduits require mining of iron and coal plus energy to transport and produce.
Fewer terminal strips. Less copper and lots less plastic.
Smaller enclosures. Since there are fewer terminal strips, there is no need for machine-mounted terminal strip enclosures and since there are fewer IO modules, the controller cabinet can be smaller. Less steel or aluminum for the enclosures reduces mining and especially energy consumption in manufacture.
Less time for installation. The contract electricians drive fewer times to the plant, transporting less equipment, saving gas… ok, maybe, I’m stretching it now. Although there are definitely more hard-to-quantify benefits lurking after installation. I don’t have the actual data to quantify the rest of these either, but I suspect they are significant.
Kermit was wrong. It is easy to be green. Just use a fieldbus.
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