1、ANSI/ASABE S626 SEP2016 Landscape Irrigation System Uniformity and Application Rate Testing American Society of Agricultural and Biological Engineers ASABE is a professional and technical organization, of members worldwide, who are dedicated to advancement of engineering applicable to agricultural,
2、food, and biological systems. ASABE Standards are consensus documents developed and adopted by the American Society of Agricultural and Biological Engineers to meet standardization needs within the scope of the Society; principally agricultural field equipment, farmstead equipment, structures, soil
3、and water resource management, turf and landscape equipment, forest engineering, food and process engineering, electric power applications, plant and animal environment, and waste management. NOTE: ASABE Standards, Engineering Practices, and Data are informational and advisory only. Their use by any
4、one engaged in industry or trade is entirely voluntary. The ASABE assumes no responsibility for results attributable to the application of ASABE Standards, Engineering Practices, and Data. Conformity does not ensure compliance with applicable ordinances, laws and regulations. Prospective users are r
5、esponsible for protecting themselves against liability for infringement of patents. ASABE Standards, Engineering Practices, and Data initially approved prior to the society name change in July of 2005 are designated as “ASAE“, regardless of the revision approval date. Newly developed Standards, Engi
6、neering Practices and Data approved after July of 2005 are designated as “ASABE“. Standards designated as “ANSI“ are American National Standards as are all ISO adoptions published by ASABE. Adoption as an American National Standard requires verification by ANSI that the requirements for due process,
7、 consensus, and other criteria for approval have been met by ASABE. Consensus is established when, in the judgment of the ANSI Board of Standards Review, substantial agreement has been reached by directly and materially affected interests. Substantial agreement means much more than a simple majority
8、, but not necessarily unanimity. Consensus requires that all views and objections be considered, and that a concerted effort be made toward their resolution. CAUTION NOTICE: ASABE and ANSI standards may be revised or withdrawn at any time. Additionally, procedures of ASABE require that action be tak
9、en periodically to reaffirm, revise, or withdraw each standard. Copyright American Society of Agricultural and Biological Engineers. All rights reserved. ASABE, 2950 Niles Road, St. Joseph, Ml 49085-9659, USA, phone 269-429-0300, fax 269-429-3852, hqasabe.org ANSI/ASABE S626 SEP2016 Copyright Americ
10、an Society of Agricultural and Biological Engineers 1 ANSI/ASABE S626 SEP2016 Approved September 2016 as an American National Standard Landscape Irrigation System Uniformity and Application Rate Testing Proposed to ASABE by the Irrigation Association; adopted by ASABE September 2016; approved as an
11、American National Standard by ANSI September 2016. Keywords: Distribution uniformity, Landscape irrigation, Audit, Catch can test, Drip irrigation, Soil moisture 1 Purpose and Scope 1.1 This standard provides methods for evaluating the application rate and/or uniformity of coverage of installed land
12、scape irrigation systems. The landscapes covered include continuous areas of turf or small ground cover, or other areas where irrigation coverage is unimpeded by the landscape materials. The methods described in this standard provide a representation of the performance of the irrigation system at th
13、e time of the test. It may or may not be representative of the everyday performance of the system. The methods may be used as part of an overall irrigation system audit. Accuracy of the results depends on the quality of measurements and data provided by the end user. 2 Definitions 2.1 sprinkler: For
14、 purposes of this standard, sprinkler refers to a landscape irrigation sprinkler that operates as a rotor, impact, or spray device, including the nozzles. Also sometimes called a head or sprinkler head. Where the term rotor is used, it shall apply to an impact sprinkler or sprinklers with multi-stre
15、am multi-trajectory rotating nozzles. 2.2 test area: geographic area of the irrigated landscape that represents the entire area of interest. 2.2 drip irrigation: a type of microirrigation using emitters that discharge water in a small uniform flow or trickle. Drip irrigation emitters dispense water
16、at a flow rate of less than or equal to 6.3 gallons per hour (24 liters per hour) when operated at 30 psi (206.8 kPa). 2.3 soil moisture meter: a sensor used to determine the amount of water in the soil. For the purposes of this standard, it refers to a portable sensor (probe), not one that is perma
17、nently installed. 2.4 catch device: a container for collecting water dispensed by the irrigation system. The device may have markings to determine volume, or may be emptied into another container for measurement. Sometimes known as a catch can. 3 Sprinkler Distribution Uniformity Testing The followi
18、ng procedures are for measuring the delivery of water from multiple sprinklers applying water to a common area. The distribution uniformity test shall be performed during normal operating conditions. If the test is not performed during normal operating conditions, an assessment of the impact of thes
19、e testing conditions compared to normal operating conditions shall be included in the report. 3.1 Determine the test area. Establish the boundaries of the test. The test area may be served by a single sprinkler zone or multiple overlapping zones. ANSI/ASABE S626 SEP2016 Copyright American Society of
20、 Agricultural and Biological Engineers 2 3.1.1 Test areas less than 200 ft2may not produce statistically valid results. See Table 1. 3.1.2 “Linking” (using information from one station or zone and applying to another) may be used when there are a large number of sprinkler zones that are identical, i
21、.e. the same sprinkler head, nozzle, spacing, operating pressure and irrigating similar soil and plant types. The auditor may elect to perform catch device tests on one-third to one-half of the sprinkler zones to get an average value that could be applied to all sprinkler zones that are identical. 3
22、.2 Catch device description and location. A minimum of 24 catch devices shall be used. All catch devices used for any one test shall be identical. They shall be such that the water does not splash in or out. The catch devices shall be of adequate size such that no device overflows during the test. T
23、he size and type of catch device shall be identified and recorded on the data sheet. Catch devices shall be uniformly distributed throughout the test area. 3.2.1 The position of all catch devices shall be maintained such that the entrance portion is level. 3.2.2 The above ground height of the top of
24、 any catch device shall be a maximum 25 cm (10 in.) above the ground and shall not interfere with the stream of water. If the test area is bordered by a hardscaped surface, the catch devices along the edge of the test area shall be placed 12 to 24 inches in from the edge. 3.2.3 Approximate catch dev
25、ice location and layout, relative to the tested sprinklers, shall be documented. See Table 1 for guidance on distance from sprinklers and maximum spacing between catch devices. 3.2.4 Catch device layout and placement. Examples of possible catch device placement relative to sprinkler heads and each o
26、ther are shown in Figures 1-5. Any catch device should be placed at least 30.5 cm (12 in.) from any sprinkler. Note that catch devices appearing on sprinkler heads Figures 1 and 2 are diagrammatic and shall be placed to match the requirements in Figures 3-5. Figure 1 Catch device layout on a rectang
27、ular area ANSI/ASABE S626 SEP2016 Copyright American Society of Agricultural and Biological Engineers 3 Figure 2 Catch device layout on an irregular area Figure 3 Catch device placement relative to sprinkler heads 3.2.5 Catch device height. Catch devices shall be placed so that they do not interfere
28、 with irrigation water. Figure 4 shows an incorrect placement with spray hitting the side of the catch device. Figure 5 shows correct placement of the catch device in the same location. Figure 4 Incorrect placement of catch device Figure 5 Correct placement of catch device ANSI/ASABE S626 SEP2016 Co
29、pyright American Society of Agricultural and Biological Engineers 4 The numbers in Table 1 for minimum suggested test period may need to be adjusted based on the capacity of the catch device, the application rate of the sprinkler, and the specific requirements of the landscape. For example, if the l
30、andscape cannot tolerate that much water, a shorter test period may be used. Test periods closer to the actual sprinkler run times for normal operation will provide a better representation of sprinkler performance. A larger catch device may be required for longer run times. For rotors, every attempt
31、 should be made to have complete rotations during the test. Table 1 Test area, catch device spacing, and test period Test Area Maximum Catch Device Spacing Minimum Number of Catch Devices between Sprinklers (not including devices near sprinklers) Minimum Suggested Test Period (full circle/half circl
32、e) Fixed spray Minimum of 200 ft27 feet 1 3 minutes/3 minutes Rotor, 305070 ft centers Minimum of 4200 ft220 feet 3 15 minutes/10 minutes 3.3 Record wind speed and direction. Wind speed during the test shall be less than or equal to 8.05 km/h (5 mph) 3.3.1 Wind movement during the test period shall
33、be determined with a rotating cup anemometer or device of equal or better accuracy. The wind direction shall be determined with a wind vane indicating at least 8 points of the compass. 3.3.2 Wind velocity sensing equipment shall be located at a minimum height of 1.0 m (3.25 ft). 3.3.3 The wind sensi
34、ng equipment shall be located outside the wetted area and at a location that is representative of the wind conditions at the sprinkler location. The maximum distance of the sensor location shall not exceed 45 m (150 ft) from the wetted area of the sprinkler under test. It is recommended that wind ve
35、locity be recorded continuously during the test period on a chart recorder. If continuous recording equipment is not available, wind velocity measurements shall be taken at the beginning, halfway through the test period and at the end of the test period or at 5 min intervals, whichever is less. 3.4
36、Measure and record sprinkler operating pressure. Pressure shall be measured and recorded using the appropriate pressure testing device at normal operating conditions at the sprinkler nearest the zone valve and the sprinkler highest and/or furthest from the zone valve. Pressure tests shall not interf
37、ere with the catch device test results. 3.5 Test run time. Test run times shall be consistent and appropriate for the sprinkler type, arc, and nozzle type, and shall be recorded. Test run times shall be adjusted for site-specific conditions and to account for matched precipitation rates. When the te
38、st area contains multiple stations, all stations or zones in the test area shall be run as part of the test. The test run times for each station or zone shall be adjusted to achieve a matched precipitation rate across the test area. 3.6 Distribution uniformity lower quarter. Calculate the low quarte
39、r distribution uniformity (DUlq) and express the result as a decimal fraction. Average catch of lowest quarter=Average catch overalllqDUCalculate sprinkler application rate using catch device data. ANSI/ASABE S626 SEP2016 Copyright American Society of Agricultural and Biological Engineers 5 If the c
40、ollected water is measured as a volume of water in milliliters: =3.66avgr CDVPRT Awhere: PR = precipitation rate (inches per hour) 3.66 = conversion factor Vavg = average volume (milliliters) Tr = test run time (minutes) ACD = area of catch device throat (square inches) If the collected water is mea
41、sured as a depth of water in inches or centimeters: =60avgrDPRTwhere: PR = precipitation rate (inches per hour or centimeters per hour) Davg = average depth of water (inches or centimeters) 60 = minutes per hour Tr = test run time (minutes) 4 Landscape Drip Irrigation System Performance Test 4.1 Equ
42、ipment inspection. The auditor should inspect and check the following items for a new or an existing drip irrigation system and record the information 4.1.1 Pressure regulator, if it is installed, record the pressure setting and flow rate of the regulator. 4.1.2 Filter or strainer downstream from th
43、e valve and prior to any drip emission devices. 4.1.3 Flush plugs, if they are installed, at the end of any runs of tubing. 4.1.4 Identify the types and flow rates of emitters that are installed. 4.2 Performance tests 4.2.1 Pressure check. This test shall use appropriate pressure check devices to ve
44、rify that a reasonable amount of pressure is present along the entire length of tubing for emission devices to work correctly. Take pressure readings just downstream of the pressure regulator and then at the end of the longest run of tubing. Record the pressures. Note: Pressure loss in excess of 20%
45、 of the pressure at the regulator indicates a potential problem with the system. Pressures outside the operating range of any pressure-compensating devices may cause device malfunction. 4.2.2 Flow test. Figure 6 shows an example water meter assembly and test setup. Figure 7 shows a typical water met
46、er and how measured quantities are displayed. ANSI/ASABE S626 SEP2016 Copyright American Society of Agricultural and Biological Engineers 6 A dedicated water meter or a temporary water meter that can be inserted into the drip zone will help determine the application rate of the drip irrigation syste
47、m. Identify the location of the water meter whether if it is a dedicated or temporary meter. Activate the drip irrigation zone and wait a few minutes until the drip system is fully charged and operational. Take a beginning meter reading using the most precise resolution reading the meter is capable.
48、 Allow the drip zone to run at least 15 minutes and then take an ending meter reading. Calculate the flow rate into quantity per hour (QPH) based on the meter readings. meter reading end - meter reading start= 60test run ti me (minutes)QPHNote: Q would reflect the units that the meter is measuring.
49、Measure the area of landscape or planting bed that the drip zone is supplying water so an application rate can be determined. This area should be the intended area of irrigation, and cover at least the plant canopy area. Over time, the canopy area will change as plants mature which will effectively lower the precipitation rate. When plant canopy is 75% or greater, set the area to be the boundary of the entire irrigated plant space, including gaps in the canopy between plants. Determine an appl
