Installing sprinklers and controllers in an area without AC power has always been a difficult and frustrating problem for contractors. There was a time, some years ago, when it couldn’t be done. Advancements in technology have given rise to options that were not available twenty years ago. Today, there are three choices, each filling its own specialized niche and falling into self-defined categories. We have ambient light, solar power, and battery operated.

The non-AC powered, battery-operated controllers can be broken down into two categories — valve box controllers and commercial- grade field controllers. In this article we will concentrate on field controllers.

The LEIT (pronounced light), manufactured by DIG Corporation, is powered by extremely low light levels or direct sunlight, and is referred to as an ambient light controller. A common mistake is to refer to these as solar controllers, one that the manufacturers quickly correct.

“The controller is powered by any kind of light, needing only a very short time of daily exposure,” explained Rick Heenan, regional sales manager for DIG Corporation. “Charging up from such a low light level makes this ideal for shaded areas or regions that frequently have overcast and cloudy skies.”

All power is provided by an internal, ultra-high efficiency photovoltaic module and microelectronic energy management system. These controllers currently operate four to sixteen stations; however, by year end 2001, reveals Heenan, a new X series will be introduced that will operate up to 28 stations.

The LEIT has all the standard features of AC powered controllers: independent programs for each valve, bilingual software in English and Spanish, non-volatile memory, monthly budget, rain delays and status reports for past and current months, etc.

An obvious application for this type of controller is for use on median strips or long strips of highway where there is no access to AC power. Municipalities also find them advantageous to use, according to Heenan. “There are many applications where it’s too costly to install a meter just for the purpose of irrigation. A good example is pocket parks.”

He explained that these parks are located in the heart of a city where there are public or low-cost housing projects, and where an apartment building had been torn down and replaced with a park. The city put in hardscapes, turf, swing sets, half-court basketball and much more. This is an excellent example of where these types of units make a perfect application.

The LEIT is a stand-alone, pedestal-mount controller and for security, a locked stainless steel enclosure is offered. For further security in the parks, municipalities have built locking enclosures for them. The highway department doesn’t always build enclosures specifically for this use; however if there’s an enclosure already there, such as for backflow, they’ll use it for added protection.

The IBOC Plus, manufactured by Irritrol Systems, is a hybrid commercial controller. It has a unique combination of battery only or battery and solar power options. This controller is available in four, eight and twelve stations with the standard features of AC-powered controllers, odd/even 365-day calendar, non-volatile memory, rain delay, program review, etc.

What’s unique about the IBOC Plus is the solar converter module, the SPC-2. “This is either mounted on top of the controller or can be mounted up to 1000 feet away from the controller, and requires two hours of direct sunlight per day to be fully charged,” says Keith Shepersky, brand manager for Irritrol Systems.
“The SPC-2 module is backward compatible to the IBOC controller, which is no longer available but still in use,” Shepersky explained. “The IBOC Plus uses a 24-volt battery, the IBOC uses a 6-volt battery.”

For security, there’s a steel cabinet with a key-locking door. The solar panel is also secured in a steel frame, which is bolted to the steel cabinet of the controller. Irritrol offers a pedestal mount for a stand-alone application or it can be wall mounted, as long as the solar panel is always facing south.

Sturman BG, LLC manufactures the Cloud IX controller. It is powered by a battery that is continually recharged by a detachable solar panel. With the solar panel detached, the controller can be mounted in any convenient location, with the panel placed in any location that gets sunlight. The solar panel is attached to the controller with wire.

The Cloud IX is completely sealed from all elements. It has no buttons or knobs, and it operates using a magnet with programming capabilities of up to four programs and twelve separate zones. A security code is entered prior to accessing the controller’s programming, which makes this unit virtually tamper-resistant.

The third category of non-AC powered field controllers is unique because it uses neither ambient light nor solar, but is fully battery powered. Once again, we want to reiterate that there are a number of battery-operated controllers on the market. For the purpose of this article, we want to address commercial-grade field controllers.

What sets the Alex-Tronix BCS, ENERCON and Smart-Alex controllers apart from other battery-powered units is the patented battery powered technology. “We haven’t created a new battery,” explained George Alexanian, owner of Alex-Tronix, “We’ve taken a Lithium battery and managed the way the power in the battery is utilized, overcoming the constraints of the battery’s life.”
“We received a grant from the U.S. Department of Energy to develop energy-efficient control systems,” commented Alexanian. “Originally, it was to develop a module that requires less energy to operate solenoids. It evolved into developing a battery-operated multi-station unit with at least five years of battery life and the capability of operating a valve up to five miles away using 14-gauge wire.” The battery life and distance on the BCS was independently tested at The Center for Irrigation Technology (CIT), at California State University, Fresno.

The BCS is offered in five and ten station models. As with the LEIT and the IBOC, the BCS has the standard features offered on AC-powered controllers, as well as a pedestal mount and locking steel cabinet for protection from theft and vandalism.

Recently, Alex-Tronix introduced the Enercon, a four and eight station battery-operated field controller. This unit operates valves up to 2,000 feet away and utilizes their patented longer battery-life technology, without the need for a module to operate the latching solenoid.
About seven years ago, L. R. Nelson purchased Solar Rain from a European company. This allowed Nelson to enter the battery-operated segment of the market.

In addition to a unit with up to six zones, L. R. Nelson’s Solar Rain offers a single battery-activated unit controller that attaches directly to the valve. The controller, power source, and DC latching solenoid is all in one. Their new 8014 Duralife Solar Rain has a 3.6 volt Lithium battery that has a ten year life.
Nelson also offers a radio activated battery unit as well.

Non-AC-powered field controllers aren’t necessarily marketed as energy saving units, because irrigation controllers have relatively low-power consumption. Municipalities look at non-AC controllers as a way to stretch their budget. According to Heenan, at one time they were allowed to hook into the power supply used for traffic lights. Now, they are no longer allowed to use this power supply. Rather than go to the expense of having a meter installed and running power, they have found a solution to an otherwise very expensive problem.

In today’s sometimes demanding, always hectic business of irrigation, you don’t have time to dwell on the “impossibles” of life. When confronted with a situation where there’s no AC power, it’s not pleasant to think of approaching your client with the expense of having a meter installed and running power. However, with these options available, you can give a reasonable bid on the job.

November December 2001