CIT - Certified Irrigation Technician Electrical Systems and Wiring 2

Question 1

An irrigation technician measures 28 VAC at the controller's zone terminal but only 18 VAC at the solenoid in the field. What is the most likely cause?

Accepted Answer

Excessive voltage drop due to long wire runs or undersized wire

Answer

A 10 VAC drop between the controller and the field solenoid indicates excessive voltage drop in the field wiring. This is typically caused by wire runs that are too long for the gauge of wire used, poor splice connections, or corroded wire.

Question 2

What is the standard operating voltage for residential and commercial irrigation solenoid valves in North America?

Accepted Answer

24 VAC

Answer

Standard irrigation solenoid valves operate on 24 VAC (volts alternating current), supplied by a transformer in the controller that steps down 120 VAC household power to 24 VAC. This low voltage is safe for direct burial wiring.

Question 3

When using a multimeter to test an irrigation solenoid, a reading of OL (overload/infinity) on the ohms scale indicates:

Accepted Answer

An open circuit — the solenoid coil is broken

Answer

An OL or infinity reading on the resistance (ohms) scale means there is no electrical path through the solenoid coil — it has an open circuit. The coil wire inside the solenoid has broken, and the solenoid must be replaced.

Question 4

The common wire (often white) in an irrigation system serves what purpose?

Accepted Answer

It provides the return path for electrical current from all solenoids back to the controller

Answer

The common wire provides the return electrical path from all solenoid valves back to the controller. It is shared by all zones, while each zone has its own individual wire from the controller to its solenoid.

Question 5

What type of wire splice connection is recommended for direct burial irrigation applications?

Accepted Answer

Waterproof grease-filled wire connectors (gel-filled)

Answer

Waterproof grease-filled (gel-filled) wire connectors are the standard for direct burial irrigation splices. The dielectric grease seals out moisture and prevents corrosion, ensuring reliable long-term connections in wet soil conditions.

CIT - Certified Irrigation Technician Practice Test

CIT - Certified Irrigation Technician Practice Test

CIT - Certified Irrigation Technician Electrical Systems and Wiring 2