Free IMSA Traffic Signal Field Technician II Exam Flashcards

A mast arm is a rigid arm on a pole. A span-wire system suspends equipment from tensioned messenger wire between supports; each needs its own approved hardware and inspection approach.

A HAWK beacon is a pedestrian crossing treatment that remains dark until activated, then uses a prescribed signal sequence to stop road traffic for the crossing phase.

A rectangular rapid-flashing beacon supplements a pedestrian crossing warning by drawing drivers' attention with an alternating flash pattern. It does not display a steady traffic-signal indication.

Aim a signal head so its intended users can see the indication clearly while unintended approaches have minimized visibility. Follow the approved plan and agency standard.

A pedestrian push button sends a call to the controller. It requests service but does not by itself determine whether the controller can immediately display a walk indication.

Inspect mounting, fasteners, cable support, seals, visibility, and physical damage. Correct deficiencies using the agency's procedures before they become a safety or reliability issue.

A raceway provides a protected path for conductors. Its routing, fittings, fill, and separation must follow the approved drawings and applicable electrical requirements.

A pull box provides access for pulling, splicing where allowed, inspecting, and maintaining underground conductors. Keep it accessible and manage drainage and debris.

Excess tension, sharp bends, abrasion, or incompatible pulling methods can damage insulation and create faults that may not appear until after the installation is energized.

Verify the foundation location, elevation, hardware, concrete condition, and cure requirements against the approved plans before placing a signal support.

A reliable splice has the correct conductor preparation, listed connector or method, insulation restoration, strain relief, and enclosure protection for its environment.

Test wiring, equipment operation, detection, indications, and documented settings before release. A passed visual inspection alone does not prove system function.

Do not treat an unapproved field change as a minor convenience. Record the condition and obtain the responsible agency's direction so drawings and assets remain accurate.

Identify all energy sources, follow the approved control-of-energy procedure, and verify the safe condition before contacting equipment. Stored and backfeed energy matter too.

Voltage equals current times resistance: V = I × R. Use it only with known, compatible units and a sound understanding of the circuit being measured.

Electrical power is P = V × I. A load drawing more current than expected may indicate a problem, but diagnose the circuit rather than assuming the cause.

Voltage drop is the loss of voltage along a conductor caused by current flowing through resistance. Long runs, small conductors, poor terminations, and high current can increase it.

Before measuring, use a meter and leads rated for the environment, inspect them, select the correct function and range, and connect at the correct test points.

A service disconnect provides a means to isolate equipment from its supply. It is part of safe servicing, but follow the complete control-of-energy procedure rather than relying on a switch position alone.

An inductive loop detector senses a change in inductance caused by a vehicle's metal mass. Loop condition, lead-in wiring, detector settings, and pavement damage can affect performance.

Presence detection holds a call while a road user remains in the detection zone. Passage detection is intended to register movement through a zone; controller use determines the operational effect.

Video detection can be affected by lighting, weather, shadows, occlusion, camera position, and configuration. Verify the field view and settings before replacing hardware.

Radar detection uses radio-frequency energy to detect movement or presence, depending on the device. Aim, mounting, environment, and configuration affect its detection zone.

A pedestrian call should be verified from the button through the controller input and programmed response. Check accessibility features and agency requirements during the inspection.

Start with the reported symptom, then check power, wiring, field device condition, input status, configuration, and controller response in a logical order.

The controller cabinet houses the equipment that applies programmed logic, routes power and inputs, monitors operation, and interfaces with field devices and communications.

A load switch is the cabinet output device that applies power to a signal load when commanded. It is not the device that decides phase timing.

A flasher produces the flashing operation used when the intersection is placed in flash. Verify the required flash pattern and field indications after service.

A monitor supervises critical signal outputs and timing relationships for unsafe conditions. When it detects a programmed fault, it can place the system into a safer state.

Label and document conductors, terminals, and equipment state before disconnecting. Good identification makes restoration and later troubleshooting safer and faster.

An uninterruptible power supply can maintain selected signal operation during a utility outage for a limited time. Verify battery condition, load plan, alarms, and transfer function as specified.

Bus-interface and serial-interface units exchange status and commands among compatible cabinet components. Confirm the cabinet standard, addressing, wiring, and configuration before diagnosing a communications fault.

After replacing a cabinet component, restore connections, verify configuration, test the related field function, and document the change. A successful power-up is not a complete repair check.

A phase is the portion of a signal cycle assigned to a compatible traffic movement or pedestrian movement. Phasing determines which movements can receive service together.

Cycle length is the time required for a coordinated sequence to repeat. Changes affect available green time, coordination, and all timing relationships.

Offset is the time relationship between coordinated intersections. It is selected to support progression for the intended travel pattern, not simply to make nearby signals change together.

Actuated control adjusts phase service using detector inputs within programmed limits. Verify detector operation before changing timing values to solve an apparent timing complaint.

Preemption interrupts normal operation to serve a special event such as an emergency or railroad movement. Priority modifies normal operation to improve service without the same level of interruption.

Save and identify the approved existing configuration before changing controller programming. It provides a recovery point and a record for review.

State what is failing, where, when, and under what conditions before testing. A precise symptom helps separate a field-device fault from a cabinet, programming, or communications problem.

Change or test one relevant variable at a time when practical. Multiple simultaneous changes can hide the cause and make a repair impossible to verify.

Scheduled inspection, cleaning, functional checks, and records help find degrading equipment before it becomes an emergency outage or unsafe operation.

At a malfunctioning intersection, first protect workers and road users using the agency's incident and traffic-control procedures. Technical diagnosis follows a safe, controlled work area.

For an intermittent fault, collect time, weather, load, alarm, and event details. Patterns often reveal whether the cause is power, connection, configuration, or a field device.

Verify normal, detection-driven, flash, and any affected special operation after a repair as appropriate. Then document the observed result and final configuration.

An asset record identifies equipment, location, configuration, condition, and service history. Accurate records support maintenance planning, troubleshooting, and replacement decisions.

Record the symptom, checks performed, fault found, parts or settings changed, tests completed, time, and any follow-up needed under the agency's process.

Configuration records let technicians compare the field condition with the approved design, restore a known-good setup, and review changes after a recurring problem.

Close out a work order only after the work, testing, documentation, and required notifications are complete. An incomplete record shifts risk to the next technician.

If a condition cannot be safely corrected in the field, secure the area as directed, notify the responsible authority, document the condition, and follow the emergency response procedure.