Central Control: Ask the Right Questions

Sorting through the various types of irrigation control systems available on the golf market has always been a difficult task. In the past, it was easier to see which product may be better than another as there were major differences between the various manufacturers. It was also easy to choose between 2-wire (decoder) or field controllers based on your management style. However, with today’s technologies and competitive environment, the waters have become murkier and as a result the decision is tougher, both in terms of what type of control system and whose product to purchase.

Today’s irrigation control system is still your basic computerized central controller operating off a database and communicating with sprinklers out in the field. However, the equipment from the computer out provides for many more options than in the past. Is it hard wired, radio or a combination of the two? In a combination system, where instead of having the interface(s) in your maintenance facility office, they are installed remotely in the field communicating with the central by radio and hard wired to the sprinklers or controllers from the interfaces. This significantly shortens communication cable runs and reduces the amount of grounding needed as there is less communication cable that needs to be protected. If you are considering a 2-wire/decoder, there are lots of options today. The decoder or module can be off the sprinkler in a valve box, attached to the sprinkler case, in the sprinkler case or part of the sprinkler valve solenoid. Which is the best choice for your course, your pocketbook and your sanity?

With a decoder/2-wire system, there are fewer wires than with a field controller system, but it is a different type of wire. Having one more expensive wire running throughout the course versus a single inexpensive wire for each sprinkler doesn’t take much math to figure out which costs less, but there is also the cost of field controllers versus the cost of decoders and a high percentage of the wire savings from a conventional field controller system could/should be used to increase the lightning protection on a decoder/2-wire system. On the decoder/2-wire systems, the grounding requirements are manufacturer driven, but it is wise to supplement it for a less troublesome system and longer life. Lightning protection should consist of a number of different pieces of equipment – not just a grounding rod. Appropriate equipment includes grounding plates, surge suppression devices, cable fuse devices, exothermic connections and shield/bond wires.

It was only several years ago the irrigation industry was starting to talk about system integration and the central control system being interactive with the pump system. Now integration has become a big part of the control system decision making process. The integration questions to ask the seller of a potential central control system include:

• Will the control system talk/integrate with a pump station? Which manufacturer’s pump system can each manufacturer’s central controllers integrate with and what will the integration get you? Minimally you want pressure, flow and pump status information.
• Will the central communicate with soil moisture sensors permanently installed on the golf course? Do the sensors have their own software or is it part of the central control system software? How is the sensor communicating back to the central controller? Is it wired or wireless or both? Can the software adjust the irrigation schedule automatically?
• What are the central controller’s remote control options? All the manufacturers have handheld radios with a million key strokes to do what you want, but in today’s day and age shouldn’t you be able to operate your system from a smart device? Does the manufacturer have an app?
• Do you want to have a weather station and connect to it from the central control system? Do you run wire to it or use radio? Is a weather station still the best investment for getting weather data for your course or is an app or other type of sensing equipment better?
• If you have an existing lightning detection system or purchasing a new one, do you want to have it interact with the irrigation controls to disconnect communication and power connections during electrical storms?

You must consider these questions before choosing a central control system and associated technology. But it’s not that easy. Systems continue to change rapidly as the irrigation industry follows other industries. That’s good for golf course irrigation, but you will also find that the control system will obsolete itself quickly. Make sure you don’t start behind with a new purchase by asking the right questions.