PowerPoint Presentation

Calibrating your Spray equipmentWisconsin Pesticide Applicator Training ProgramUniversity of Wisconsin Extension1 of 40Calibration2014Calibrating Your Spray EquipmentIn this section of your Private Applicator Training we will discuss the calibration of field sprayers. We will:Look at a number of factors which affect application ratesGo through the calibration process in your manualAsk you to work through some calibration examples.

Although there are a number of equally effective ways to calibrate a field sprayer, the method weve chosen is relatively simple yet provides enough information for you to understand why. This method is different than the method featured in the past. It is not any more difficult than the previous method, but is one of the most common ways to calibrate a field sprayer.

1Purpose of Calibration

To deliver the correct rate of pesticideANDApply it uniformly over the target areaPhoto source: Syngenta2 of 40Calibration2014Purpose of CalibrationFirst, we might want to understand why were calibrate. We calibrate to ensure that your equipment delivers the correct rate of pesticide uniformly over the target area. Thus, from the very definition, one can see that calibration is more than just mathematical calculations because it involves equipment maintenance as well. Calibrating your equipment provides a great opportunity to assure that it is working properly.

It is illegal to use or offer for use pesticide application equipment that is leaking or in disrepair, or which cannot be properly calibrated.

But one of the most compelling reason to calibrate is . . .2Purpose of Calibration

Errors can lead to crop injury or loss of money3 of 40Calibration2014Purpose of CalibrationTo prevent errors that can lead to crop injury, loss of money or environmental damage.3Mini-Sprayers and Pattern

Each nozzle is a mini-sprayer1. Nozzle/boom height2. Nozzle angle3. Nozzle spacing4 of 40Calibration2014Mini-Sprayers and PatternYou can think of the nozzles on your sprayer as a group of mini-sprayers each one delivering spray mix across the width of the spray swath. You want each nozzle to apply the same volume of spray mix over the entire distance that the sprayers travels in the field.

There are three things that affect spray pattern.

1. Nozzle/boom height to low and you might get gaps between spray bands, to high and you may get to much overlap and drift.2. Nozzle angle Nozzles used in agriculture typically come in 80 degree angel or 110, but other angles can be found. Also, nozzles are often put at a 10 degree angle on the boom. This is so that the spray pattern from one nozzle does not interfere with the pattern of the nozzle next to it.3. Nozzle Spacing This will affect the height you will with to have the boom.

Most nozzle manufactures will provide information regarding the optimum boom heights and pressures that their nozzles should be used.4Spray Rate

Nozzle flow rateSpeed of travel

5 of 40Calibration2014Spray RateThere are two variables that affect over all spray rate. Nozzle flow and speed of travel. Lets break these two down further.5Spray Rate Nozzle Flow RateNozzle flow rateSpeed of travelPressure

OK for small adjustmentsHave to increase 4x to double output

6 of 40Calibration2014Spray Rate Nozzle Flow RateThe nozzle flow rate is affected by your operating pressure and the size of the nozzle opening. Increasing pressure or using a nozzle with a larger opening will increase the flow rate.

However, increasing pressure will NOT give you a proportional increase in flow rate. For example, doubling the pressure does not double the flow rate; rather, you must increase the pressure fourfold to double the flow rate. Therefore, pressure cannot be used to make major changes in spray rate. Keep in mind that operating pressure must be kept within the recommended range for each nozzle type to obtain a uniform spray pattern and to minimize drift.

Adjusting pressure is good for small adjustments of flow; however, for larger adjustments consider changing the nozzle.

6Spray Rate Nozzle Flow RateNozzle flow rateSpeed of travelFor larger changes in output, consider changing the nozzle

Gallons per minute - GPMXR 80 03

80 degree angle0.3 GPM at 40 psi7 of 40Calibration2014Spray Rate Nozzle Flow RateIncreasing the size of the nozzle opening will allow more liquid to pass through the nozzle.

At this point it might be beneficial to talk a little about nozzles and how they are identified. When a company makes nozzles, they design them to put a certain amount of liquid out over a specified amount of time. Although there may be some manufactures that might identify their nozzles in a different way, many measure rate by gallons per minute (GPM). A manufacturers quality assurance will work to be consistent in this output at a specific pressure.

In the nozzle example we have shown here the identification number is XR 8003. What does this mean? It means that it is an Extended Range, a model name that gives some information about the nozzle. In this case, this nozzle holds its pattern in a extended range of pressures. However, 8003 provides two bits of information also. The first is that this nozzle has an 80 degree pattern angle, which would affect the boom height. The second is that it will put out 0.3 gallons per minute at 40 psi. The 40 psi is something that would be specified by the manufacturer.

Knowing the amount a nozzle will put out in GPM will become important when we discuss the actual calibration of the application equipment.7Spray Rate Speed of TravelNozzle flow rateSpeed of travel

One to oneSpeed up put less outEasy way to make changes8 of 40Calibration2014Spray Rate Speed of TravelThe second variable that affect spray rate is speed. Changing the speed of the application equipment is another way you can make large changes in spray rate. The nice thing about changing speed is that it is a one to one relationship. Increase your speed time 2, from 5 mph to 10 mph, divide your output by 2, from 20 gallons per acre (GPA) to 10 GPA. This can be an easy way to make changes to output. However, speed is often determined by the equipment you are using and the conditions of the location you are spraying.

Most application equipment have speedometers of various kinds. However, mechanical slippage and wear and tear that computers systems may not pick up on can lead to inconsistencies in speed. It is always a good idea to check speed once in a while to confirm accuracy.8Spray Rate Speed of TravelNozzle flow rateSpeed of travel

Speed (MPH) = distance in feet x 0.68 time in seconds9 of 40Calibration2014Spray Rate Speed of TravelTo measure ground speed steak out a distance between 200 feet to 800 feet. It is best to do this in conditions similar to your spraying location. Use 200 feet for speeds 5 miles per hour (MPH) or less, 400 feet for speeds 5 to 10 mph and 800 for speeds above 10 mph. Half fill the tank with water and drive from one steak to the other then back again, timing both trips. Using the average time in seconds, plug the numbers into the equation speed in miles per hour equals distance in feet divided by time in seconds times zero point six eight.

Zero point six eight is a constant that converts feet per seconds into miles per hour. It is important that you use feet and seconds in your measurements when using this equation, for if you use feet per minutes, then the constant will give you a wrong answer.

OK, we have covered the variable that affect spray rate and we have been introduced to a little math with calculating our ground speed. Now, lets move into actually calibrating spray equipment.9The 4 steps to Calibration1. Determine Required Flow Rate

10 of 40Calibration2014The 4 Steps to CalibrationIn this method of calibration, we propose 4 basic steps to calibrate application equipment for a broadcast application.

The first is to determine the required flow rate.10The 4 steps to Calibration1. Determine Required Flow Rate2. Actual Flow Rate Uniformity of Flow Rate

11 of 40Calibration2014The 4 Steps to CalibrationThe second is to measure the actual flow rate. This at the same time will also determine the uniformity of the flow rate. Are all the nozzles putting out the same amount at the same rate?11The 4 steps to Calibration1. Determine Required Flow Rate2. Actual Flow Rate Uniformity of Flow Rate3. Adjust to Flow Rate

12 of 40Calibration2014The 4 Steps to CalibrationThe third step is to make any adjustment to achieve the required flow rate. As mentioned these adjustments to a required flow rate will also assure that each nozzle is within 5% error of each other.12The 4 steps to Calibration4. Determine how much pesticide and water to add to the tank1. Determine Required Flow Rate2. Actual Flow Rate Uniformity of Flow Rate3. Adjust to Flow Rate

Calibration2014The 4 Steps to CalibrationThe fourth step is to determine how much pesticide and water to add to the tank.

Lets go through each of these steps.131st Step Determine Flow Rate

MPH - Decide speedGPA - Gallons per Acre are given by labelW - Nozzle spacing in inchesGPM = MPH x GPA x W 594014 of 40Calibration20141st Step Determine Flow RateThe first step in this process is to calculate what each nozzle should be putting out. This equation GPM equals MPH times GPA times width of the nozzles (W) all divided by 5940 is one of the most powerful equations in calibrating spray equipment. MPH is often determined by the spray conditions and the equipment capabilities. The GPA is given by the pesticide of choice label and W stands for the nozzle width in inches. The number 5940 is another constant that converts all the units to gallons per minute. As with the equitation for calculating ground speed it is important that the units are consistent in this equation. If your nozzle spacing is in millimeters, then the answer will be wrong.

Also note that it is convenient that we are calculating gallons per minute for this is how most nozzle manufacturers label their nozzles.141st Step Determine Flow Rate

GPM = MPH x GPA x W 5940Example: Wish to spray Whoop-IT. The label says to apply at 1 pt/A in 15 to 20 GPA. You wish to travel at 8 MPHGPM = 8 MPH x 15 GPA x 15 5940GPM = 0.3 This is your required flow rate15 of 40Calibration20141st Step Determine Flow RateLets use this equation in an example. You wish to spray the herbicide Whoop-IT. The label says to apply 1 pt/A in 15 to 20 GPA. You wish to travel at 8 MPH. Take the equation and plug in the numbers. The answer is 0.3 gallons per minute. This is your required spray rate for that speed to deliver 15 GPA.152nd Step Actual Flow Rate

Required flow rate is 0.3 GPM

If all your nozzles are within 5% error of 12.8 fl oz in 20 seconds . . .Youre Good To Go!16 of 40Calibration20142nd Step Actual Flow RateIf we catch within 5% of the required spray rate, between 13.4 and 12.2 from each nozzle we are good to go. Catching this amount from each nozzle also lets you know that each nozzle is putting out equally.

We should be so lucky. In many cases we will have to make adjustments.162nd Step Actual Flow Rate

Required flow rate is 0.3 GPM

But if you are NOT within 5% of your required flow rate then . . .You actually collect

8.5 fl oz in 20 sec 0.2 GPM17 of 40Calibration20142nd Step Actual Flow RateLets throw a monkey wrench into this scenario. Our required spray rate we calculated is 0.3, but we dont have any 03 nozzles, we only have 02s.

In this case we would actually collect 8.5 fl oz in 20 seconds. Out output is greater than 5% error of our required spray rate. When we back calculate 8.5 fluid ounces in 20 seconds we find that we are actually putting out 0.2 GPM.173nd Step Adjust Flow Rate

Speed

GPM=MPH x xGPAW594018 of 40Calibration20143rd Step Adjust Flow RateAdjusting speed is a simple way to adjust output. Lets go back to the original equation we used to get our required spray rate. We can manipulate this equation to provide to give us a new speed to travel at that will provide us with the required spray rate.183nd Step Adjust Flow Rate

Speed

MPH=W x GPA5940xGPM19 of 40Calibration20143rd Step Adjust Flow RateIn this adjusted equation, we have MPH equals 5940 times GPM divided by nozzle width times the GPA we wish to put out at.

Plug in the numbers and see what we get?193nd Step Adjust Flow Rate

Speed

MPH=15 inches x 15 GPA5940x0.2 GPM5.3 MPH20 of 40Calibration20143rd Step Adjust Flow RateWhen we plug the numbers in and run the math we find out that if we traveled at 5.3 MPH we would still be putting out 15 GPA with the 0.2 GPM that we caught with the nozzles we are using. Traveling at 5.3 might make for a long day and inefficient if you have many acres to cover.

If we kept everything the same, our speed and ran with out actual spray rate of 0.2 GPM, what would our GPA be?203nd Step Adjust Flow rate

SpeedGPA

GPM=MPH x xGPAW594021 of 40Calibration20141st Step Determine Flow RateOnce again, we can manipulate that equation to provide what GPA we would actually be putting out if we kept everything the same.213nd Step Adjust Flow rate

SpeedGPA

GPA=15 inches x 8 MPH5940x0.2 GPM10 GPA This is below the label15 to 20 GPA rate range22 of 40Calibration20141st Step Determine Flow RateLets plug the numbers in. We find after running the math that our actual spray rate of 0.2 GPM would give us a GPA of 10 if we traveled at 8 MPH. If we remember back to the beginning of this example the product label dictated a GPA of 15 to 20. This would mean that we would have to make adjustments to achieve the GPA stated on the label.

If our calculations provided a GPA that was in the range provided by the label and there were no efficacy issues connected to this GPA, we might be OK with the output. If you accept a different GPA than you originally planned, remember that this will have an affect on the amount of product in the tank, which leads us to step four.224th Step Amount to Add

You must know:

The product rateThe required spray rate (GPA)Tank capacity of or field size23 of 40Calibration20144th Step Amount to AddStep 4 in calibrating is to calculate the amount of product that will go into the tank. To do this, there are some things that you must know. First, what is the rate that you wish to apply the product at? This is determined by the label. You need to know your desired spray rate in GPA. Most labels provide a range of spray rates, but this is usually provided by the label. Finally, you need to know the tank capacity of field size.

Lets put this into an example.234th Step Amount to Add

500-gallon tankSprayer is calibrated at 20 GPA32 fl oz Glyphosate 41 per acreHow much ofGlyphosaste 41 do youadd to the tank?24 of 40Calibration20144th Step Amount to AddIn this example we have a 500 gallon tank and we have calibrated our sprayer to deliver 20 GPA. We are going to use 32 fl oz of Glypphoste 41 per acre. How much Glyphosate 41 do you add to the tank?244th Step Amount to Add

Step 1: how many acres will each tankful sprayAcres per = 500-gal tank = 25 acres tank 20 GPA25 of 40Calibration20144th Step Amount to AddFirst calculate the number of acres that can be covered per tank. In our example, a 500 gallon tank applying at 20 GPA, we will be covering 25 acres.254th Step Amount to Add to a Full Tank

Step 2: how much Glyphosate 41 to add to each tank?Product per= 25 acres x 32 fl oz/A tank= 800 fl oz 6 gal + 2 pt26 of 40Calibration20144th Step Amount to AddAppling to 25 acres at 32 fluid ounce per acre we would simply multiply the number of acres to the acre rate. We will be adding 800 fl oz to the tank. This converts to 6 gallons and 2 pints. Because we want 500 gallons of mix we would deduct this from the amount water to put in the tank. Depending on your operation, the measuring capability may not be accurate to the pint, but most can get to the gallon or pretty close.264th Step Amount to Add to a Partial Tank

15-acre fieldSprayer is calibrated at 20 GPA12 fl oz/A of Headline fungicideHow much ofHeadline do youadd to the tank?27 of 40Calibration20144th Step Amount to Add to a Partial TankIn this example we are applying only to 15 acres. The GPA is still 20 GPA and this time we are applying 12 fl oz/A of Headline fungicide. How much headline do we add to the tank?274th Step Amount to Add Partial Tank

Step 1: how much water to add to the tank?Water per= 15 acres x 20 GPA tank= 300 gals of mix28 of 40Calibration20144th Step Amount to Add Partial TankIf we are not going to be using the full capacity of the tank then use the acreage that you are going to be spraying multiplied by the gallons per acres, 15 acres multiplied by 20 GPA. In our example, we will be mixing up 300 gallons of mix.

284th Step Amount to Add to a Partial Tank

Step 1: how much Headline?Product per = 15 acres x 12 fl oz per acre tank

= 180 fl oz 1 gal + 3.2 pt29 of 40Calibration20144th Step Amount to Add to a Partial TankWe will use the acres again to calculate the amount of product to add to the tank. In our example 15 multiplied by 12. We will be adding 180 fl oz to our tank, which works out to be on gallon 3.2 pints.

In many cases the label recommends some form of adjuvant. 294th Step Adjuvant Rates

Rate expressed as product per Acre

Rate expressed as a percentageAmount needed = product rate x acres= 2 pts crop oil x 16 acres= 32 pts (4 gals) Amount needed = percentage x gals spray mix= 0.25% x 250 gals 100= 0.625 gals adjuvant 5 pts30 of 40Calibration20144th Step Adjuvant RatesThere are two ways that labels give adjuvant rates. The first is expressed by product per acres. For example 2 pts per acres. Simply multiply by the number of acres. We get 32 pints in the tank to to apply to 16 acres.

The second way in which adjuvant rates are given is as a percentage of the mix. For example if we are mixing 250 gallons and we are going to add 0.25% Nonionic surfactant. We would divide the percentage by 100 and multiply it by the number of gallons we wish to mix. In our example it works out to point 625 gallons, which converts to 5 pints.30

Calibrating your GranularApplicator31 of 40Calibration2014Calibrating Your Granular ApplicatorNow lets take a look at calibrating a granular applicator; specifically, the insecticide hoppers on your corn planter.31Granular Applications Ounces per 1000 ft of row

30 row 2.5 ft 43560 ft2 = 17,424 ft long 2.5 ft for an acre2.517,424 ft32 of 40Calibration2014Granular Applications Ounces Per 1000 ft of RowFor this type of granular application, product rates are commonly expressed as ounces per 1,000 ft of row. Insecticide labels also provide a table which converts ounces per 1,000 feet of row to pounds per acre to help you determine the total amount of product to purchase. For example, 8 ounces per 1,000 feet of row at 30 row spacing equals 8.8 pounds per acre. For row spacing not shown in these tables, there is a formula on page 196 of your manual for making those conversions.

When doing this type of calibration, it is beneficial to think of each hopper applying to a linear acre. A row spacing of 2.5 ft would have to be 17,424 feet long to equal 1 acre.

32Granular Applications Ounces per 1000 ft of row

2.517,424 ft1000 ft x 8.8 lbs = 0.5 lb 8 ozs per 17, 424 ft 1000 ft33 of 40Calibration20141st Step Determine Flow RateTo calculate the amount to put down on a 1,000 feet of that linear acre, simply take 1,000 ft times the rate per acre, divided by the linear length of the application for 1 acre. This gives us 8 oz per 1,000 ft.

Luckily the label has already done this for us.33Granular Applications Ounces per 1000 ft of row

Step 1: Mark a distance of 1,000 feet in the fieldStep 2: Adjust each hopper unit to recommended settingsStep 3: Ready the hopper units for measuring outputStep 4: Drive the measured distance34 of 40Calibration2014Granular Applications Ounces Per 1000 ft of RowTo calibrate, first measure and mark a distance of 1000 feet in the field. The terrain should be similar to that of the area to be treated.

Adjust the settings on each unit based on recommendations in the owners manual or on the granular product label.

Fill the hoppers with the product you will be applying, turn the units on, and operate them until all are feeding. Turn them off, disconnect the drop tubes, and attach a container (e.g. plastic bag or jar) to the outlet of each applicator.

Drive the measured distance, operating at the speed you intend to use during the application.34Granular Applications Ounces per 1000 ft of row

Step 5: Weigh material from each unitUnit12345678Weight (ounces)8.28.47.67.98.18.28.66.035 of 40Calibration2014Granular Applications Ounces per 1000 ft of rowAs shown here, weight and record the amount of material collected from each hopper; if necessary, be sure to subtract the weight of the container.35Granular Applications Ounces per 1000 ft of row

Step 6: Adjust units not within 5% of the recommended rate of 8 ozFive percent of 8 ounces is:8 ounces x .05

Recalibrate units whose output is:less than 7.6 ounces orgreater than 8.4 ounces36 of 40Calibration2014Granular Application Ounces Per 1000 ft of RowCompare the weight collected from each unit to the acceptable range in output. To calculate the acceptable range in output, multiply the recommended rate of 5 ounces by 5%, or 0.05. In our example, the acceptable deviation is 0.4 ounce, so each unit should have applied within the range of 7.6 and 8.4 ounces.36Granular Applications Ounces per 1000 ft of row

Step 5: Weigh material from each unitUnit12345678Weight (ounces)8.2 8.47.67.98.18.28.66.0

XXAcceptable Range in output 7.6 8.4 ounces37 of 40Calibration2014Granular Applications Ounces Per 1000 Ft of RowHopper units 7 and 8 are outside of the acceptable range and you will need to adjust them and recalibrate.37Why calibrate, I have one of these?

38 of 40Calibration2014Why Calibrate, I have one of theseFor those of you who use an application control system, spray rate is maintained. Speed is also maintained by various mechanisms. You will still need to calculate the amount of product to mix into the tank.

Even with these technologies it is not a bad policy to check the accuracy of what is actually coming out the nozzle.38Why calibrate I have one of these?

It is always a good idea to check:Equipment wears outEquipment can be offConstants in the computer may be wrongSlippage can lead to the wrong speedAnd . . .39 of 40Calibration2014Why Calibrate I have one of these?Equipment can wear out. Agricultural equipment takes a beating in the day to day use. In some cases, the level of precision required for this equipment can falter due to conditions that the equipment have to work in.

Much of this equipment depends on mathematical principles that use constants that are either input at the factory or behind the wheel. These inputs can sometimes be default or entered wrong.

Slippage can take precise equipment out of exact working order. Blockage of pluming or valves can lead to less than obvious issues.

And it is not always a wise policy to take thinking out of the picture, just because the . . . 39Why not make sure it is working?

GPS Gone Wrong!What DID you do Father!?!The gizmo said to turn RIGHT!40 of 40Calibration2014Why not make sure it is working? just because the machine gave you an answer.40Calibrating your Spray equipmentPesticide ApplicatorTraining(608) 262-7588PATPROGRAM@WISCMAIL.WISC.EDUHTTP://IPCM.WISC.EDU/PATMainMenuCalibration201441