Application Equipment and Calibration Flashcards
7 cards from real CFA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Application Equipment and Calibration flashcards as text
An injection system for liquid fertilizer is calibrated to inject at a 1:128 ratio. If the carrier flow is 10 gallons per minute, how many ounces per minute is the concentrate being injected?
Answer: 10 oz/min
At 1:128 ratio, 10 gal/min carrier = 1,280 oz/min; inject rate = 1,280 / 128 = 10 oz/min.
What maintenance procedure helps prevent corrosion in fertilizer application equipment after use with ammonium-based products?
Answer: Triple-rinsing with clean water and neutralizing with a mild base solution
Thorough rinsing removes corrosive fertilizer residues, and neutralizing helps prevent ammonium salt deposits that can pit metal surfaces.
What is the function of a pressure regulator in a fertilizer sprayer system?
Answer: To maintain consistent operating pressure independent of pump speed variations
A pressure regulator maintains consistent boom pressure by bypassing excess flow back to the tank when pressure exceeds the set point.
When calibrating a variable-rate technology (VRT) applicator, what additional step is required compared to calibrating a fixed-rate applicator?
Answer: Verifying that the controller accurately adjusts output across the entire rate range in the prescription map
VRT applicators must be verified across the full range of rates because accuracy at one rate does not guarantee accuracy at others.
A fertilizer applicator travels at 5 mph with a boom width of 30 feet and a target rate of 20 gallons per acre. What total flow rate (gal/min) must the system deliver?
Answer: 4.5 gal/min
Area per min = (5 x 5,280 x 30) / (43,560 x 60) = 0.2273 ac/min; flow = 0.2273 x 20 = 4.55 gal/min.
Which of the following best describes 'streaking' caused by improperly calibrated rotary spreaders?
Answer: Visible lines of over- and under-application parallel to the direction of travel
Streaking appears as parallel bands alternating between high and low nutrient concentration due to gaps or overlaps in the spread pattern.
A granular fertilizer spreader is calibrated on a paved surface. Which important factor must be accounted for when extrapolating results to field conditions?
Answer: Field ground speed may differ from speed on pavement, altering actual application rate
Rough or soft field conditions often cause ground speed to differ from calibration speed, directly affecting the amount of material applied per unit area.