Controllers set scene for reactive, predictive automation

Irrigation controllers used to be simple programmable boxes. Now, new-generation units are remotely operated brains, capable of self-adjusting settings in response to past, current or future conditions. And, as John Power reports, the trend towards automation is sure to penetrate the entire outdoor power equipment market.

Sophisticated irrigation controllers have been around for some time – remember the Hardie Micro Master Irrigation Controller, which for years helped grounds managers achieve significant water savings via targeted watering regimes?

A weather station.
The latest controllers can be linked to either to personal weather stations or online weather services like Weather Underground.

Today, the latest controllers not only respond to manually programmed settings, but they can also react automatically to a whole range of contingencies based on weather station data, soil moisture levels, changes in flow rates, wind, and even local laws affecting permitted watering times or days.

In other words, modern controllers are able to adapt to their immediate environment in ways that were unthinkable before the advent of Wi-Fi interconnectedness and mobile phones and tablets.

Tony Shepley, Sales & Marketing Director for Nelson Irrigation, which specialises in Hunter Irrigation equipment, says the latest irrigation controllers are part of a truly global network of operating systems.

“The most technologically advanced system we use is Hydrawise™, which is a cloud-based platform,” Mr Shepley said. “It’s a Wi-Fi-connected controller designed for residential use through to commercial applications like sporting fields and council properties.

“Obviously, you can remotely program a unit from anywhere at any time, but the bigger deal is the ability to take weather data from weather stations and average that out for your particular area. Or, you can take it one step further and set up the controller to do some ‘predictive’ watering; for example, you might set up normal running times, and then put in some additional parameters about how you would like the system to adjust its own normal settings under different conditions.”

A simple example of self-adjustment, Mr Shepley said, might relate to forecasts for high temperatures – a system could automatically extend watering times by a certain percentage every time a forecast high temperature threshold was exceeded. At the other extreme, it might switch off watering completely (or just postpone watering for a day, etc) whenever freezing temperatures were forecast. The unit’s adjustments, as mentioned, are fully variable and defined by whatever ‘parameters’ (high and low thresholds, triggered by specific conditions or sensor inputs) that the user chooses to implement.

The effectiveness of a controller, therefore, is only as good as the reliability and sensitivity of the information it receives. With that in mind, Mr Shepley says a great deal of work is underway to ensure that weather data, for instance, is as accurate and relevant as possible.

“When you program the controller you can choose to take weather data from a particular weather station,” he explained, suggesting proximity is usually the defining factor. “Or you could make use of Hydrawise’s virtual weather station, which takes data from all sorts of areas – satellites, airports and airplane data, or pressure readings from phones.”

Controllers can also be connected to privately operated weather stations, which can often be beneficial in areas of highly variable and localized weather patterns, or in very remote areas.


While remotely controlled, automated irrigation functions may sound impressive, what do they actually achieve in terms of water savings?

“It’s up to 50 per cent savings,” Mr Shepley said. “It goes without saying that the ultimate aim is to save water.”

However, water savings are not the only advantages of using ‘smart’ controllers. Lower water consumption equates to lower wear and tear and electricity consumption of pump apparatus, which can be costly on properties that are not serviced by mains water. Similarly, reducing watering times and avoiding hazards like icy or frosty ground conditions can enhance the lifespan of valves and sprinkler heads.

New-generation irrigation controllers can respond automatically to a range of sensor-based data.

Another important benefit of remotely operated and heavily automated controllers relates to small-to-medium contractors, who might be responsible for the watering systems of 20, 50 or more customers. The ability to monitor and control a large number of watering systems from a central location means a contractor can see instantly if there are any anomalies in customers’ systems, particularly if properties are equipped with flow meters.

“With the Hydrawise platform a contractor can manage all customers’ controllers on the one platform, and if there are any issues the controllers can send alarms,” Mr Shepley said.

Events that might trigger an alarm include lost connectivity, unscheduled watering, wiring or coil problems, as well as leak detections. “It means a contractor can manage customers’ systems and fix a problem before the customer knows there is a problem.”

For serious commercial operators, yet another advantage of using advanced controllers relates to the abundance of diagnostic data collected over the life of the system. Detailed data can help grounds staff to refine watering regimes by offering clear information about how watering settings relate directly to turf quality and health. Data can also point to local climatic changes, which might be useful when establishing or justifying budgets for additional plant or dam infrastructure.

According to Mr Shepley, these kinds of features are invaluable, particularly in drought-affected areas where every drop of water – and every dollar – needs to be conserved.

The good news for owners of older irrigation systems is that contemporary controllers can usually be retrofitted without too much hassle. Controllers are inexpensive and, in the case of Hydrawise systems, can be linked to as many as 54 stations.


Many readers will appreciate that irrigation systems are not the only physical assets that can be linked to weather stations and other sensors.

A sensor beneath the ground.
The ability to respond automatically to soil moisture readings and other sensor-based technologies has changed controller functionality forever.

While irrigation has led the way in ‘smart’ controller operability, mainly due to the static and sizeable nature of the installed equipment, there are new ranges of remotely controlled, robotic outdoor power equipment that are equally amenable to ‘smart’ Wi-Fi functionality.

New generations of robotic mowers (like the Worx Landroid), for instance, are being designed to react to external conditions based on weather station data and other sensors, in exactly the same way that modern irrigation systems do. 

Consider this scenario: a weather station predicts heavy rainfall in two hours’ time. This reading instantly triggers the following automated actions involving different equipment:

  • The scheduled bi-weekly watering cycle is postposed to the following day.
  • The scheduled daily mowing of the lawns is brought forward, so it can be completed before the rain arrives.• The scheduled daily mowing of the lawns is brought forward, so it can be completed before the rain arrives.
  • Water from a full tank is diverted to another tank so every drop of rainwater can be collected from the imminent downpour.

These kinds of simultaneous actions raise challenging questions for our industry. For example, should we be anticipating the need for shared operating platforms that can handle different product ranges from different companies, thereby avoiding the time-wasting clumsiness of lots of separate platforms?

The problem of interconnectivity between different classes and brands of products is not new – indeed, managers of commercial buildings have long experienced dealing with interconnected, sensor-based services like air conditioning, blind and awning operation, lighting, as well as security functions, all of which can be run from a single building management system. The most common shared platform for such applications is KNX, which is a free, open-source platform used by hundreds of manufacturers globally. By using a common platform like KNX, building managers can use any brand or model of appliance they wish (providing it conforms to KNX protocols), and know that the new unit will fit seamlessly into the existing management control system.

Perhaps members of the outdoor power equipment industry will have to embrace a similar open-source platform in the near future!

Sprinklers watering a golf course.