CIT - Certified Irrigation Technician Certified Irrigation Technician Controllers and Programming 1 — Questions and Answers
Question 1: A technician is programming a controller with three programs (A, B, C). Which scenario best describes the correct use of multiple programs?
- Run all zones on the same schedule regardless of plant type
- Assign turf zones to Program A with frequent short cycles and shrub zones to Program B with less frequent deep cycles (Correct answer)
- Use Program C exclusively for drip zones since drip systems require the most water
- Set all programs to the same start time to ensure uniform watering across the property
Correct answer: Assign turf zones to Program A with frequent short cycles and shrub zones to Program B with less frequent deep cycles
Multiple programs allow different irrigation schedules tailored to each plant type's water needs. Turf typically needs frequent, shorter cycles while shrubs benefit from less frequent but deeper watering, making separate programs the correct approach.
Question 2: When using a cycle-and-soak programming technique on a controller, the primary goal is to:
- Reduce the total volume of water applied to each zone
- Allow water to infiltrate before applying more, preventing runoff on sloped or clay soils (Correct answer)
- Ensure each zone receives water at exactly the same rate
- Eliminate the need for a rain sensor by breaking cycles into smaller increments
Correct answer: Allow water to infiltrate before applying more, preventing runoff on sloped or clay soils
Cycle-and-soak splits a zone's total run time into multiple shorter cycles separated by soak periods, giving water time to infiltrate and preventing surface runoff — especially important on slopes or compacted soils with slow infiltration rates.
Question 3: A homeowner reports that their controller skipped several scheduled watering days after a large storm. The most likely cause is:
- A blown fuse in the controller's transformer circuit
- The controller's seasonal adjust feature was automatically reduced to 0%
- An active rain sensor or weather-based skip that suspended irrigation after detecting sufficient rainfall (Correct answer)
- The master valve solenoid failed and disconnected the programming memory
Correct answer: An active rain sensor or weather-based skip that suspended irrigation after detecting sufficient rainfall
Rain sensors and smart weather-based controllers are designed to skip or suspend scheduled irrigation when rainfall meets or exceeds a set threshold, preventing unnecessary watering after a significant storm event.
Question 4: What does the 'seasonal adjustment' (or 'water budget') feature on an irrigation controller allow a technician to do?
- Add or remove irrigation zones without rewiring the controller
- Globally increase or decrease all zone run times by a percentage to account for seasonal climate changes (Correct answer)
- Automatically detect the soil type and adjust flow rates accordingly
- Override individual zone schedules during peak demand hours
Correct answer: Globally increase or decrease all zone run times by a percentage to account for seasonal climate changes
The seasonal adjustment feature applies a global percentage increase or decrease to all zone run times, allowing easy adaptation to seasonal changes in evapotranspiration without reprogramming each zone individually.
Question 5: A 2-wire decoder-based irrigation controller differs from a conventional multi-wire controller primarily because:
- It uses AC power at each decoder instead of low-voltage DC signals
- Each solenoid valve is assigned a unique address and all valves share a single two-wire communication path (Correct answer)
- It cannot support more than 12 zones due to signal degradation
- Decoder systems require a separate controller module for each irrigation zone
Correct answer: Each solenoid valve is assigned a unique address and all valves share a single two-wire communication path
In a 2-wire decoder system, all valves connect to a single two-conductor cable, and each decoder receives a unique digital address. The controller sends addressed signals along the shared path to activate specific valves, greatly reducing wiring complexity on large systems.
Question 6: A technician notices the controller's display shows 'SENSOR OPEN' or a similar fault. The appropriate first diagnostic step is to:
- Replace the controller's main circuit board immediately
- Check the rain or flow sensor wiring for breaks, corrosion, or a sensor bypass jumper that may be missing (Correct answer)
- Reprogram all zones from scratch to clear the fault code
- Increase the transformer voltage to overcome the sensor resistance
Correct answer: Check the rain or flow sensor wiring for breaks, corrosion, or a sensor bypass jumper that may be missing
A 'SENSOR OPEN' fault typically indicates the controller detects an open circuit at the sensor terminal, which is most commonly caused by broken wiring, a corroded connection, or a missing bypass jumper when no sensor is installed. Inspecting wiring and connections is the correct first step.
CIT - Certified Irrigation Technician Certified Irrigation Technician Controllers and Programming 1
A technician is programming a controller with three programs (A, B, C).
Which scenario best describes the correct use of multiple programs?