Two-wire, field controllers and plenty of facts

Features - Irrigation

Considering an irrigation system enhancement? Ian Williams offers a checklist to guide your course’s decision.

April 16, 2019

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It’s time to make a decision. You have already spent months, maybe years, educating your club members and staff on why the golf course will benefit from replacing the current outdated and inefficient irrigation system. The club has allocated the funds necessary for such an expense, and membership has voted or your owner has signed off. You have met with irrigation consultants, designers, suppliers, contractors, manufacturers and all other stakeholders interested in the club’s foray into the future. How you got to this point with your sanity intact is a whole other story.

What you are now faced with is a decision of whether you select a more conventional field controller irrigation system or the increasingly popular two-wire controlled system. This decision is typically made before plans are created, specifications are prepared, and bids are solicited. Sometimes it is required to solicit pricing for both types of systems.

So, what is the difference between the two control systems? You want to make an educated decision and select the best fit that will meet the needs of the club and your maintenance schedule, as well as follow the project’s budget guidelines. Your decision will impact the club for years to come. As a professional manager and responsible club representative, you want to make a decision that will take the club and its investment far into the future.

In simple terms, a field-controlled irrigation system is one in which the sprinklers are activated by a controller, usually placed somewhere on the golf course. They are usually located within line-of-site of the golf hole, but there are circumstances where the controllers may be hidden from sight. Sometimes the club will go as far as to wall mount them in structures on the golf course in an attempt to hide any evidence of an irrigation controller on the course. Most controllers can store start times and run times, as well as provide manual operation of the sprinklers assigned to them. Sprinklers are directly wired back to the field controller. The quantity of sprinklers per controller is limited by the model. Ideally, the controllers are linked to a central control computer that allows for flow management and automatic scheduling.

In a two-wire irrigation system, sprinklers are directly connected to a wire path.
© ian Williams

A two-wire system, or satellite-less system, on the other hand, has very few or no controllers on the golf course, and the sprinklers are directly connected to a wire path. Depending on the manufacturer, the wire path can host many sprinklers and the sprinklers are spread out over a great distance. The term two-wire is referring to the fact that the wire path consists of two conductors.

More recently, hybrid systems are available that incorporate controllers in their two-wire system. Acting as an interface, these controllers, which have a programmable faceplate, can operate independently of a central computer but still utilize a wire path that connects to each sprinkler and provides both power and communication to and from the sprinkler.

Different manufacturers provide many options of two-wire and field controller systems, but we are not talking about manufacturers at this point. We are weighing the pros and cons of a two-wire system and a field controller system so that you can make an educated decision. Consider this a checklist of questions and data points you want to answer so you can make an informed decision.

1. Stay open

Do not go into this decision close-minded and relying on what you are already comfortable with. If we all went about our daily lives in that manner, we would still be using flip phones and listening to vinyl records. This decision is not only for you. You are selecting the best options for your club and its long-term goals. You could also be selecting a system for the next superintendent depending on your current situation. This is a 25-plus-year decision. You do not want to box yourself in with only what you are comfortable with before performing your due diligence. Don’t shy away from learning everything you can about the latest technology available.

2. Consider a consultant

Have you employed the help of an irrigation consultant? Irrigation consultants will offer an objective view from years of experience with different brands and the different styles of systems available today. An irrigation consultant specializes in design and specifications, as well as different manufacturers’ equipment. They know the different types of systems well and can answer those burning questions while helping you separate fact from fiction.

3. Use your network

Talk to your peers. Talk to the courses in your area that have upgraded or replaced their irrigation systems. What do they like? What do they dislike? If they had to do it all over again, would they make the same decisions? What would they do differently? Do they feel they got the system they were promised? Is the system performing as they expected? Most superintendents are more than happy to discuss the ins and outs of the decisions they made during the process. Don’t be afraid to ask.

A field-controlled irrigation system is one in which the sprinklers are activated by a controller, usually placed somewhere on the golf course.

4. Try before buying

Take the systems for a test drive. This may entail visiting a few courses. Your peers will most likely be more than happy to host you and allow you to spend time with them looking at software or hardware and going through the system with them and their staff. This is an opportunity to get a first-hand feel for the different types of systems.

5. Set goals

Write out your goals and expectations with a new irrigation system. Is it to reduce water use? Is turf health your top priority? Does ease of use mean anything to you? Is it all the above? With a new irrigation system, you are getting a new hydraulic delivery system regardless of the type of control system you select. Think of your control goals. Do you expect to operate solely from a tablet or mobile device? Does the idea of some sort of in-field control appeal to you?

6. Service matters

Understand your support network. Who is there to service and troubleshoot the control system if the need arises? Can your staff support issues, or will you be reliant on third-party service? What kind of downtime is acceptable to you? Understand the equipment needed to maintain the control system so that the system is always operating as designed and protected from lightning/surge damage.

7. Chat with a contractor

Contractors have experience installing the systems, troubleshooting and operating the systems. They may have personal opinions, but we are looking for the facts. Ask them about their experiences installing both types of system. What is it like to add to the system after the fact? What are the costs associated with adding sprinkler heads or landscape zones to the system down the road?

8. Be on the money

Budgets are a real thing, and when the funds are available you don’t want to risk missing the opportunity. Understand the cost differences associated with the two types of systems. Do not just consider materials, but focus on installation costs as well. Don’t stop at understanding the upfront costs. What will the control system cost your club in two years, five years or 10 years? Can you expect costly hardware and/or software upgrades for the system to stay as current as possible?

Selecting an irrigation control system is a complex decision for golf course operators and stakeholders.
Ian Williams

9. Level about looks

Are aesthetics important to your club? Both two-wire systems and field controller systems can have pedestals located on the golf course depending on the manufacturer. With two-wire systems, you have the option of the field interface/controller or just a local interface mounted adjacent to the central computer or remotely located on the course in a weather-proof environment. Some clubs have gone to great lengths to hide the field controllers from the golfer’s field of vision. Maybe hiding a pedestal is not a priority for you or the club.

10. Pay attention

to power

If you are involved in a total golf course renovation or new construction project, you will need to take into consideration that you may only have power available from one source, or no power initially for that matter. You will have to pay special attention to sequencing the installation with the type of control system you have selected. You may be operating on a temporary power source for a period, or you may not have shelter for a central control computer.

11. Think ahead

Understand your maintenance requirements now and in the future. Will there be high-voltage equipment, such as fans or wells, that you would like to operate over the irrigation control system so you can integrate smart responses from central control? Question whether the type of control system you are considering can handle that type of integration. What are the additional costs associated with this, if any?

12. Plan for the worst

Understand the redundancies of both types of control systems. What is the action if a field controller or a group of field controllers or power wire to the controllers is compromised? How can you irrigate if an interface fails or your central control software is down?

Field controllers and two-wire systems have been around for a long time. Enhancements and reliability have been improved over the years in both systems. As with any decision, there are measurable pros and cons. Writing them out is helpful, and you can add to the list as this period of exploration goes on. Seek the help of qualified professionals whenever possible. There are a number of objective consultants who have been through this scenario many times and they can help guide you through the process. Above all else, keep an open mind. Don’t be afraid of the latest technology. Unless you are still listening to Steely Dan on your Walkman, this should not be a problem.

Ian Williams, CID, is a partner with Don Mahaffey at the irrigation design and consulting firm Green Irrigation Solutions.