The American Heritage Dictionary defines the word “wireless” as “having no wires.” When most people hear the word “wireless,” they think of cell phones, Internet, television remotes and other more traditional wireless objects. Most likely, the last thing that comes to most peoples' minds is wireless pumping, monitoring, manure spreading, conveyor control or tank level monitoring. Today the definition of “wireless” has expanded to mean more than your everyday television remote control.
With the rising need for simplicity, ease of operation, reduction in the work force, and increasing rules and regulations for pump installers, simple wireless switching products can solve these problems and, at the same time, cut cost and increase efficiency.
Currently, more than 20 farms in Washington, Oregon and Idaho have been hit with heavy fines from the Environmental Protection Agency for the leakage of solid waste into nearby streams, rivers and ground water. Farmers have been forced to come up with a solution to avoid the leakage of solid waste. So now the farmers are faced with new costs for extra machinery, plus increased labor to pump the manure into the ground. It became apparent that the farmers needed to cut their costs, but still maintain the same profit margins. Some farmers turned to the use of wireless technology to increase efficiency and cut costs. These farmers found a way to control the throttle, clutches and power of diesel pumps, which they use for spreading the manure. The latest technology allows the farmer to be up to 2 miles away from the pump and still have control. Some farms have adopted wireless technology to switch between valves that control the flow of manure into different fields, using fixed transmitters and receivers instead of handheld remote controls. Some farms have incorporated programmable logic controllers (PLC) with wireless systems to make them completely automated.
Another application for wireless technology is apparent in the ground water industry. Many customers are faced with digging trenches through golf courses, housing developments, freeways and other undesirable terrain to replace faulty wires. A typical installation for this application is to install the transmitter at the water storage tank with the corresponding receiver at the well. The transmitter is wired up to a float or pressure switch (any dry contact closure) at the tank, and the receiver activates a relay at the pump. When water gets to a specified level (determined by the float or pressure switch), the transmitter will send a digital signal for the pump to come on. Once the storage tank is full, the transmitter will send another signal telling the pump to turn off. At first, most customers have a hard time accepting the use of wireless technology in an age-old industry, but after investigating the cost savings involved without having to trench and lay hundreds of feet of cable, the decision to go wireless is made easier.
Center pivot control is another application where wireless technology is needed. Many farmers are faced with trenching through prime farm land to replace faulty wires, and are forced to walk long distances to turn their center pivots on or off. Farmers now can save time by not having to drive out to each center pivot location to manually start or stop the irrigation cycle. Pivots are easily controlled from a tractor, pump house or even the office. Using a PLC in conjunction with wireless technology, farmers can now make the task of starting and stopping a center pivot completely automated. These PLCs, in conjunction with wireless switching systems, allow pumps to be controlled based on time, voltage, pressure and flow.
Innovators in the industry have devised hundreds of ways to use wireless technology to benefit everyday installations. An example of a company taking the step into wireless technology is Heartland Pump. The company has a customer that needs to add dilution water to a chemical solution 3 miles away from their main building at the discharge site. Heartland Pump decided to use a wireless solution for its customer's application. The customer was leery of using wireless technology for this application until they investigated the cost associated with running cable 3 miles. The solution was simple; when a pressure switch is triggered at the chemical pump in the main building, it will activate the transmitter, which will then send a signal to the receiver 3 miles away and activate a relay to turn on the dilution pump.
There are many different companies that manufacture wireless technology. Some focus on very complex, expensive technology that primarily is used by municipalities and other large enterprises. There are other companies that focus on simple, short range, non-industrial, garage door-style switching. Few companies fall in the middle of these two categories, offering simple wireless switching with an industrial grade product. Different technology and frequencies can offer different operating capabilities and ranges. Higher frequencies such as 900 MHz allow for a larger data exchange, known as bandwidth, while very low frequencies are less dependent on line of sight. The 900 MHz frequency has a very short wave that is easily blocked by obstacles; a good example of this would be your television remote. At higher frequencies, obstacles such as buildings, trees and hills can cause the signal to be blocked and drastically reduce the transmitting distance. Some manufacturers offer a wireless product that operates at 27 MHz. Wireless products operating at this frequency have great benefits for industrial and commercial use because they generally do not require line of sight. The 27 MHz radio wave is very long, unlike the 900 MHz, which allows the signal to bounce over obstacles more readily. The industrial wireless 27 MHz band is in the middle of the Citizens' Band (CB) radio spectrum. The extreme ranges of CB radio are well appreciated in the industrial market.
Operation of the wireless switching system is simple - connect a switch, relay or any other device with a dry contact closure to the transmitter inputs (terminal block). When a contact is closed, the transmitter will immediately send an “on” transmission to the receiver, changing the state of the selected receiver output from 0 VDC to 12 VDC. The receiver output can be used to activate a relay, solenoid, light, etc. Immediately after a contact is open, the transmitter will send an “off” transmission to the receiver, changing the state of the selected output from 12 VDC to 0 VDC, turning off the connected device.
As more customers understand the benefits of using wireless technology, more doors, which may have been closed or hard to open before, now can open. When looking at the total cost of laying wire, including time, trenching and permitting (plus headaches), wireless switching becomes a viable option. Saving your customer money and time can lead to increased loyalty and future business.