The Next Generation of Central Controllers: Commanding Communication Remotely

It was the bottom of the 17th inning on May 21, 2016, and it was getting late. At Petco Park in San Diego, California, the Padres’ Wil Myers was at the plate; he hit a foul ball and was squaring back up for another pitch when he stopped, and pointed towards right field. It had just struck midnight at one of the longest games in MLB history… and in right field, the sprinklers had come on. The game ground to a halt.

“Well, now we know what time Petco Park’s automatic sprinklers are set to go off,” wrote one sports journalist later. Eventually, the facilities staff shut the system down, allowing the Dodgers to finally wrap up the 18-inning game with a win.

It’s hard to say that the Petco Park field operations managers and groundskeepers had egg on their faces, since no one knew the game would drag on for more than five-and-a-half hours. But an irrigation snafu can be embarrassing, nonetheless.

Early central control systems would have required someone to physically go to the central control box to manually shut off the sprinklers. Fortunately, in the age of wireless central control, irrigation systems can make taming a rogue sprinkler as easy as tapping a few buttons on your smartphone. You don’t even have to be at the ballpark. In fact, with today’s technology, you don’t even have to be in the same state—or country.

The technology driving the new generation of central controllers is transforming what the term ‘central control’ even means. Traditional configurations of wires and banks of wall-mounted controllers have been upended in favor of wireless communications and cloud-based systems.

This shift is transforming the way large-scale irrigation operations are managed, aiding water-conservation efforts, and helping managers save on labor.

Central controllers are normally used for large-scale applications, like commercial projects, office parks, campuses or municipal green spaces. By grouping controllers together, central controllers streamline the process of communicating with each other. These highly specialized systems have come a long way since the days of using wall-mounted electromechanical clocks with wires going to multiple controller locations.

Automated irrigation started with hydraulic controllers, followed by electromechanical controllers, solidstate electronic controllers, and two-wire technology. Then, the technology behind the Internet of Things began to radically alter just about every facet of our lives. Smart controllers debuted, and now we have wireless, smart central controllers.

At the heart of all of these methods is communication—from the manager to the control module, to the satellite controller stations; then, communication from those stations to each of the valves.

With wireless communication making a splash in the industry of late, it may come as no surprise that cellular companies and internet service providers are making their way into the field. Communication heavies like Verizon and AT&T are becoming major players, and letting the public know that communications is what drives big irrigation, as you may have noticed from some of these companies’ recent television advertisements highlighting their role in the ag sector.

With communications being elemental to central controllers, the continually evolving methods of communications have created a paradigm shift in this area of our industry. For instance, going wireless is a big deal for irrigation managers.

“Being able to use systems that aren’t physically wired together, using the internet to channel communications, using cloud-based computing to allow somebody to connect to controllers from anyw here in the world—that’s been a huge gamechanger,” says Larry Sarver, president of Tucor, Inc.

Having your irrigation system operate on a wireless system that can be accessed and adjusted remotely is akin to being able to send a group message via text on your cell phone to your workers. Why physically visit each of them in person to relay a message if you can just shoot all of them a text at the same time? Alas, people tend to cling to established methods, even in the face of improvements over those methods. As with any new technology in the field, there’s been some predictable hesitation.

For example, Sarver recalled when he started Tucor, debuting its two-wire system in 1995. Folks in the irrigation industry didn’t readily accept the new technology. “Initially, it was like pushing a rope up a hill,” he said on the phone from his Pittsburgh, Pennsylvania office. “We introduced two-wire to the market, and got serious pushback for the first ten years. But now, it’s pretty much recognized as the technology people use in advanced systems.”

With the two-wire technology, capable of supporting up to 200 valves per controller location, the need for linking multiple controllers on a given site was often eliminated. “Having so many valves and multiple flow sensors on a single controller helped drive the initial development for internet access and, ultimately, web-based solutions,” Sarver said. And now that those web-based solutions have come to fruition, the newness may still make some in the industry balk.

Pat McCauslin, superintendent of landscaping for the University of Notre Dame in South Bend, Indiana, uses the Sentinel central control system by Toro to maintain irrigation on its sprawling campus. He admits to having some resistance to newer technology. “There was a large learning curve with it being computerized,” McCauslin says, about getting everyone up to speed. “Do we have headaches with it? Yeah, but I think you have headaches with anything that’s computer-operated.”

Nevertheless, leveraging the wireless technology has been a boon to water conservation at the Indiana campus. “It really shortened our water window down from the old days, where we were watering 24 hours a day. We’ve shrunk that down to about eight hours now.”

Jeff Coates, one of the irrigation technicians on the campus who manages the central control system, says the water savings is a result of being able to ‘micromanage’ the irrigation. For example, if a contractor on campus damages an irrigation main (which has happened ‘several times’), the system will register the overflow and close the master valve. An alert will notify the irrigation manager via his mobile device—in this case, an iPad. Coates and other campus irrigation technicians all have iPads that allow them to adjust the system from anywhere at any time. And with the quality of the turf and landscaping at the school being a major point of pride for its groundskeepers, those iPads don’t leave their sides. “That thing goes with me everywhere,” Coates says. “After hours, on vacation—everywhere.”

Besides saving water, the system also saves time. It used to take hours to shut down the irrigation system at the campus with the previous central control systems. The new system can do it in a matter of seconds.

“I’ve got 71 controllers on this campus, and ten of them on the athletic fields,” said Coates. “So I’m talking to a total of 81 controllers. That could take up the better part of an hour to send and receive. The global shutdown talks to all of the controllers in one burst, with a common address. I click on that, and in about four seconds, I’ve talked to every single controller I have out there, and shut them all down into what we call a ‘rain hold’.”

Ease of operation goes even further, if you consider the labor you save by using a wireless central control system that you can adjust remotely. “In the past, if you had to make changes to controllers throughout your entire system, you would have to send individuals to go out there,” says Sergio Ramos, product manager for Rainmaster. “The whole reasoning behind a central control system is to have eyes on all your controllers without actually having to see them, making you more responsive. All of this makes it more convenient for the manager of the irrigation system.”

As irrigation systems grow, eventually they become unduly burdensome to check on or change settings of field controllers. That is the tipping point, according to Peter Lackner, product manager for Sentinel at Toro. “If a sports field manager or a grounds guy for a city only has a couple of controllers, running around to each one of them is fine, but as a system gets bigger, it would just be easier and more efficient to have everything centrally managed. At a certain point, it becomes a no-brainer.”

Remotely-accessed central control systems also give users instant visibility about what’s going on at a site.

Russ Jundt is the founder and vice president at Conserva Irrigation, a large-scale irrigation contracting company based in Ham Lake, Minnesota. Conserva maintains the central control systems for some bigname retailers, like Walmart and Target. When Hurricane Matthew made landfall in October 2016, the central control system alerted Jundt right away. “I could tell you the exact minute that it was coming through our Target properties, because I got multiple alerts. I saw them all go into rain pause, rain pause, rain pause—one after another. I knew when it hit Orlando; I knew when it hit Tampa.”

The most contentious aspect of the new generation of central controllers comes from finding the best way to wirelessly connect the components of the system. What works for one site might not be the best choice for another. It depends on the circumstances—how many controllers there are, what the topogra- phy of the site is, and how close the controllers are to each other all play a part in the decision process. Linking everything together by radio could mean high upfront costs, but lower costs on the back end. Cellular connectivity is quick and easy, but with regular recurring costs.

“If you’ve got 50 controllers on a property, you’re more apt to want to put more capital expense upfront to install a radio infrastructure, because it’s easier to budget that under a capital project than it is to ask for money for recurring maintenance fees annually,” said Sarver.

“But a lot of people aren’t set up for that. If you’ve got one or two controllers, it makes no sense to have radio infrastructure tying two controllers together, because cellular is the quickest, fastest and cheapest method.”

In some cases, a system will rely completely on WiFi connectivity. Sarver says there’s been a big push for all-cellular, but there’s resistance to paying the recurring fees. “Trying to sort through all that is really the big battleground right now.”

But these efforts to implement a specialized central control system will fall flat if you don’t take care to make sure the equipment it’s controlling is working properly. Jundt says that overlooking the repair and maintenance of the basic irrigation system components is the biggest misstep companies make when it comes to central control. “Our humble opinion is, before you invest in this high-end technology—which is phenomenal—you have to get that system tight: zone by zone, head by head, main lines, lateral lines, all the way down to drip lines.”

“Many times, Conserva is brought in on projects after a central control system is purchased, and the property owners are wondering why they aren’t saving the 40, 50, 60 percent on water, as promised. You can have that, but you have to shore up that system, get it clean, tight, and operating—all the valves, all the solenoids, everything responding perfectly—then you can have that awesome central control.”