Managing irrigation systems for large farm fields is a challenging application. However, Acromag’s new I/O Server Industrial PC is able to apply many new technologies to provide a cost-effective solution to this agriculture problem. As a low-power, ruggedized controller with remote communication capabilities, the I/O Server is flexible to take advantage of many local energy sources (solar, wind, water, geothermal, or battery) and wireless network services. And with a powerful processor and integrated I/O modules, the I/O Server is well-equipped to monitor sensors and control the irrigation system automatically.
A variety of features make the I/O Server ideal to operate an irrigation system and many other machine control systems in remote or harsh environments. The shock and vibration-resistant, fanless computer design provides high reliability. Advanced thermal management enables operation from -30 to 75°C. Plus, flexible power accepts a 9-35V DC supply and draws less than 60W for solar power compatibility.
Effective irrigation control requires timely and accurate delivery of water to a farm field. Unfortunately, farm fields are often located great distances from regular human traffic and frequently divided into many tracts of land separated far apart from one another. A single farm may spread across state or even country boundaries making efficient operation very difficult.
To combat these challenges, an irrigation control system must:
1. properly control farm field water delivery with minimal, if any, human involvement.
2. keep management supervisors apprised of farm field status.
3. provide exception alerts when maintenance is required.
Traditionally, the decision to water or not involved actually viewing the farm field to determine if the field is adequately saturated or if it will rain. Similarly, an individual had to be on-site to open/close flow valves for water delivery and detect field problems such as leaks, plugged taps, poor water pressure, or flooding.
Managing many farm fields required many individuals, plenty of travel, and a lot of time. All of these factors contributed to higher expenses. The implementation of automation to enable programmable irrigation valve control and farm field status collection accompanied by rule-based water delivery algorithms minimizes human interaction. The resulting autonomous operation can determine watering needs, control water delivery systems, and report problems that do require attention by maintenance personnel.
1. A solar grid supplies power to the I/O Server Industrial PC (autonomous irrigation controller) and the sensor/valve network for each irrigation leg.
2. The I/O Server boots from a CompactFlash (CF) card.
3. The I/O Server collects data from all the sensors and controls valves using an RS-485 ModBus RTU and/or Ethernet Modbus/TCP network. Status reports are sent via cellular communication to the farm field management station every hour.
4. Plug-in IOS modules can provide additional analog, digital, and serial I/O processing.
5. Data from moisture sensors helps determine water needs for each irrigation leg.
6. A flow control valve on each irrigation leg regulates water delivery. Shut-off valves are used to disable an irrigation leg or all water at the main supply.
7. Irregularities in flow, valve operation, batteries, or solar charging circuits are reported to the farm field management station for human intervention.
In the system above, the farm field manager works remotely and is able to:––
1. view the irrigation status of each active farm field.
2. activate / deactivate any farm field
3. manage problems by exception
4. deploy maintenance staff to troubled sites
The status reports for a farm field require information on the:
1. farm field autonomous controller
a. farm field active (is this farm field in service?)
b. power (is the solar array properly functioning? )
c. batteries (are the batteries taking charge? charged? to what level?)
2. main water supply
a. pressure (is the water main in service and at expected performance?)
b. flow rate/volume (how much water, and at what rate, is being supplied to enabled irrigation legs?)
c. shut-off valve condition (is the water main enabled?)
3. farm field irrigation leg
a. emergency shut-off valve condition (is this leg enabled?)
b. flow valve position (what is the level of flow regulation?)
c. flow rate/volume (how much water, and at what rate, is being supplied to this leg?)
d. moisture sensors (what is the soil moisture content?)
e. power (is the solar array at the irrigation leg properly functioning?)
f. batteries (are the batteries at the irrigation leg taking charge? charged? to what level?)
To accomplish the objectives stated earlier, the autonomous irrigation controller only needs to:
1. adjust the main water supply shut-off valve
2. adjust the farm field irrigation leg
a. emergency shut-off valve
b. flow valve position (from fully-closed to fully-open)
3. identify anomalies and request human intervention (maintenance staff)
The autonomous irrigation controller is fully empowered to meet the dictates of the farm field. To guarantee proper water delivery to each irrigation leg, the moisture content for each irrigation leg is monitored and the appropriate flow valves are adjusted accordingly over the Modbus network. Problems, when and if they arise, are transmitted to the farm field management station over the cellular link. The farm field management supervisor is then able to view farm field status information in detail and, as appropriate, dispatch maintenance personnel.
Key Acromag I/O Server features:
♦ Ruggedized computer (-30 to 75°C)
♦ High reliability (fanless)
♦ 9-35V DC power with low current draw (60W max) for use with solar power
♦ Ethernet support via cellular link
♦ Easy boot via Ethernet network boot from supervisory server or CompactFlash
♦ Choice of operating system (Linux, Windows Embedded, others)
♦ Support for Modbus RTU or TCP interface for valves, flow meters, and sensors
♦ Expandable, adaptable system
♦ 7-year warranty
Acromag developed the I/O Server for distributed monitoring and control systems in challenging environments. Is the I/O Server right for your application?
Contact your local Acromag representative for more information.