IMSA Traffic Signal Senior Field Technician
II Certification Exam Questions And Correct
Answers With Rationales 2026
1. What is the primary function of a traffic signal controller?
A. To measure vehicle speed
B. To detect vehicle presence
C. To manage the allocation of right-of-way
D. To record traffic counts
The controller determines which movement has right-of-way
through signal phase control.
2. NEMA TS2 controllers are designed to communicate via which
standard?
A. Ethernet/IP
B. SDLC bus
C. RS-485
D. CAN bus
TS2 controllers use an SDLC serial communication bus for
peripheral communication.
3. Which component provides power isolation between signal load
circuits?
A. Relay board
, B. Load switch
C. Detector card
D. Flash transfer relay
Load switches isolate and control each lamp circuit.
4. What color wire is typically used for the neutral return in signal
wiring?
A. Red
B. Green
C. White
D. Black
White wires are reserved for the neutral conductor per NEC color
code.
5. A phase service flash typically activates when:
A. The controller detects a fault condition
B. The green interval extends beyond max time
C. Detector fails to actuate
D. Preemption occurs
Flash mode ensures safety by reverting to an all-flash condition
when faults occur.
6. The “Conflict Monitor Unit” (CMU) serves to:
A. Detect voltage surges
B. Detect incompatible green or walk signals
C. Measure phase timing
D. Adjust detector sensitivity
The CMU ensures no conflicting indications are active
simultaneously.
, 7. What is the proper grounding method for a signal cabinet?
A. Grounded through controller housing
B. Dedicated copper grounding electrode conductor
C. Shared with streetlight ground
D. Not required
A dedicated ground rod ensures electrical safety and noise
reduction.
8. A typical detector loop operates on what frequency range?
A. 60 Hz
B. 20–200 kHz
C. 10 MHz
D. 5 kHz
Inductive loops use oscillators in the 20–200 kHz range.
9. What is the term for extending green based on continuous vehicle
detections?
A. Delay
B. Passage time
C. Recall
D. Max time
Passage time keeps green active while vehicles continue to be
detected.
10. When a phase is in recall mode, it:
A. Always receives a service each cycle
B. Waits for detector actuation
C. Extends green time only when actuated
D. Remains skipped
Recall ensures a phase is called automatically every cycle.
II Certification Exam Questions And Correct
Answers With Rationales 2026
1. What is the primary function of a traffic signal controller?
A. To measure vehicle speed
B. To detect vehicle presence
C. To manage the allocation of right-of-way
D. To record traffic counts
The controller determines which movement has right-of-way
through signal phase control.
2. NEMA TS2 controllers are designed to communicate via which
standard?
A. Ethernet/IP
B. SDLC bus
C. RS-485
D. CAN bus
TS2 controllers use an SDLC serial communication bus for
peripheral communication.
3. Which component provides power isolation between signal load
circuits?
A. Relay board
, B. Load switch
C. Detector card
D. Flash transfer relay
Load switches isolate and control each lamp circuit.
4. What color wire is typically used for the neutral return in signal
wiring?
A. Red
B. Green
C. White
D. Black
White wires are reserved for the neutral conductor per NEC color
code.
5. A phase service flash typically activates when:
A. The controller detects a fault condition
B. The green interval extends beyond max time
C. Detector fails to actuate
D. Preemption occurs
Flash mode ensures safety by reverting to an all-flash condition
when faults occur.
6. The “Conflict Monitor Unit” (CMU) serves to:
A. Detect voltage surges
B. Detect incompatible green or walk signals
C. Measure phase timing
D. Adjust detector sensitivity
The CMU ensures no conflicting indications are active
simultaneously.
, 7. What is the proper grounding method for a signal cabinet?
A. Grounded through controller housing
B. Dedicated copper grounding electrode conductor
C. Shared with streetlight ground
D. Not required
A dedicated ground rod ensures electrical safety and noise
reduction.
8. A typical detector loop operates on what frequency range?
A. 60 Hz
B. 20–200 kHz
C. 10 MHz
D. 5 kHz
Inductive loops use oscillators in the 20–200 kHz range.
9. What is the term for extending green based on continuous vehicle
detections?
A. Delay
B. Passage time
C. Recall
D. Max time
Passage time keeps green active while vehicles continue to be
detected.
10. When a phase is in recall mode, it:
A. Always receives a service each cycle
B. Waits for detector actuation
C. Extends green time only when actuated
D. Remains skipped
Recall ensures a phase is called automatically every cycle.
