Take IMSA Bench Tech II Practice Questions - IMSA Traffic Signal Bench Technician Level II Certification Exam

QUESTION 1 / 25

In a NEMA TS1 cabinet, which connector carries the load-switch driver outputs from the controller to the back panel?

Choose one answer below.

AMS-A✓BMS-B✓CMS-C✓DMS-D✓

QUESTION 2 / 25

What is the fundamental wiring difference between a NEMA TS1 cabinet and a NEMA TS2 Type 1 cabinet?

Choose one answer below.

ATS2 Type 1 replaces the MS-A/B/C parallel wiring with an SDLC serial data bus✓BTS2 Type 1 uses higher field-output voltage than TS1✓CTS2 Type 1 eliminates the conflict monitor and load switches✓DTS2 Type 1 is wired with single-conductor 600 V cables instead of multi-conductor harnesses✓

QUESTION 3 / 25

A NEMA TS2 Type 2 cabinet is most accurately described as:

Choose one answer below.

AA TS1 cabinet with no SDLC bus✓BA TS2 cabinet that retains MS-A/B/C connectors so it can run TS1-style controllers✓CA TS2 cabinet without an MMU✓DAn ATC cabinet using ITS Cabinet v2 architecture✓

QUESTION 4 / 25

On a NEMA load switch, which output triggers when the controller energizes the green driver pin?

Choose one answer below.

APin 3 (Red field output)✓BPin 4 (Yellow field output)✓CPin 6 (Green field output)✓DPin 1 (AC neutral)✓

QUESTION 5 / 25

What component in a NEMA cabinet provides the AC-line isolation point and is required to remove all 120 VAC field output power for safe bench work on the back panel?

Choose one answer below.

AThe CMU/MMU reset button✓BThe police panel auto/flash switch✓CThe signal bus main circuit breaker (or main disconnect)✓DThe detector rack power switch✓

QUESTION 6 / 25

Which color is conventionally used for the AC equipment grounding conductor inside a NEMA traffic signal cabinet?

Choose one answer below.

AWhite✓BGreen (or green with yellow stripe)✓CBlack✓DRed✓

QUESTION 7 / 25

On a TS2 Type 1 cabinet, what is the role of the Bus Interface Unit (BIU) in the detector rack?

Choose one answer below.

AIt rectifies AC field input to DC for the detector amplifiers✓BIt packages detector amplifier call states onto the SDLC Port 1 bus for the controller✓CIt directly switches the green field load output✓DIt synchronizes coordination offsets between adjacent intersections✓

QUESTION 8 / 25

Which TS2 SDLC bus carries the controller-to-MMU and detector-rack data traffic?

Choose one answer below.

APort 1✓BPort 2✓CPort 3 (C2S serial)✓DPort 5 (Ethernet)✓

QUESTION 9 / 25

A flash transfer relay in a NEMA cabinet is energized when:

Choose one answer below.

AThe cabinet is running normal automatic operation under controller command✓BThe cabinet is placed in flash by the conflict monitor, flasher unit, or police panel✓CPreemption is active✓DCoordination is enabled✓

QUESTION 10 / 25

In TS1 cabinet wiring, which pin function on the MS-B connector lets the controller force the cabinet into flash mode for diagnostic testing?

Choose one answer below.

AStop Time input✓BManual Control Enable input✓CMMU Flash output (controller-commanded flash)✓DCoordination Free input✓

QUESTION 11 / 25

On the back panel of a typical eight-phase NEMA cabinet, how many vehicle load switches are usually installed for through and protected-left phases (excluding overlaps)?

Choose one answer below.

AFour✓BSix✓CEight✓DTwelve✓

QUESTION 12 / 25

When wiring a flashing yellow arrow (FYA) overlap, the protected-left green and the FYA permissive yellow are typically driven by:

Choose one answer below.

AThe same load-switch channel✓BTwo separate load-switch channels (one for protected green/yellow/red, one for the FYA permissive yellow output)✓CThe MMU output relay✓DA dedicated FYA relay built into the controller power supply✓

QUESTION 13 / 25

On a TS2 cabinet, what is the function of the SDLC Port 1 transient/termination panel (commonly called the bus terminator)?

Choose one answer below.

AIt blocks SDLC traffic when the controller is idle✓BIt provides a controlled impedance termination on the SDLC bus to prevent reflections and bus errors✓CIt supplies +24 VDC to the load switches✓DIt isolates the CMU from the cabinet✓

QUESTION 14 / 25

In an ITS Cabinet (Caltrans 332/ITS Cabinet v2) hosting a 2070, the role of the CMU/SIU compared to a NEMA TS2 MMU is:

Choose one answer below.

AIdentical, with the same termination program card✓BThe CMU monitors output conflict logic over a serial bus to the SIU, replacing parallel field monitoring✓CThe CMU is optional in ITS cabinets✓DThe CMU only handles ped clearance monitoring✓

QUESTION 15 / 25

Which TS2 cabinet device generates the 60 flashes-per-minute (FPM) signal used by the cabinet's flash transfer relays during flash operation?

Choose one answer below.

AThe controller's internal flash oscillator✓BThe cabinet flasher unit (two-circuit solid-state flasher)✓CThe MMU's internal red flasher✓DThe detector rack BIU✓

QUESTION 16 / 25

Which condition is most likely if a NEMA load switch has a stuck-on green output even when the controller is calling red?

Choose one answer below.

AThe load switch internal triac/SCR has failed shorted✓BThe MMU is in startup mode✓CThe cabinet ground is missing✓DThe detector rack is mis-addressed✓

QUESTION 17 / 25

What is the maximum normal AC line-input voltage range a properly fused NEMA cabinet's signal bus is designed to operate within?

Choose one answer below.

A75 to 95 VAC✓BApproximately 95 to 135 VAC nominal 120 V service✓C180 to 220 VAC✓D200 to 250 VAC✓

QUESTION 18 / 25

Which NEMA cabinet term refers to the wire bundle that goes from the back-panel field terminals out to the signal heads, loops, and pedestrian pushbuttons?

Choose one answer below.

AService-entrance conductors✓BField cable✓CMS harness✓DSDLC trunk✓

QUESTION 19 / 25

What advantage of the Model 2070 controller over the Model 170 controller is most relevant for a bench technician evaluating cabinet upgrades?

Choose one answer below.

AIt uses CMOS instead of TTL field outputs✓BIt runs a real-time operating system with a defined ATC API and supports newer application software✓CIt eliminates the conflict monitor✓DIt requires no external load switches✓

QUESTION 20 / 25

Which standard formally defines the Advanced Transportation Controller (ATC) platform that 2070 ATC and modern NEMA controllers comply with?

Choose one answer below.

AAASHTO LRFD✓BATC 5201 / ATC 5401 family of standards✓CASTM E2213✓DIEEE 802.11p✓

QUESTION 21 / 25

A traditional Type 170 controller most commonly runs which controller application program?

Choose one answer below.

ACaltrans BiTran 233 / Wapiti / similar 170 software✓BLinux with Java app✓CWindows IoT✓DVxWorks with NTCIP 1202✓

QUESTION 22 / 25

A 2070 controller typically uses which CPU module to host the application program?

Choose one answer below.

A2070-1A / 2070-1B / 2070-1C CPU module✓BPentium 4 desktop processor✓CZ80 with no RAM expansion✓DDSP coprocessor only✓

QUESTION 23 / 25

Which 2070 input/output module is the field-output module that interfaces the controller to the cabinet load switches in a Caltrans 332 cabinet?

Choose one answer below.

A2070-2A (Field I/O Module C1)✓B2070-7A (Async serial)✓C2070-3B (Front-panel display)✓D2070-4A (Power supply)✓

QUESTION 24 / 25

When loading new firmware on a 2070-ATC controller, which interface is most commonly used in modern field practice?

Choose one answer below.

AFront-panel keypad-only entry of hex bytes✓BUSB or Ethernet port for firmware upload✓CEight-track tape drive✓DRS-485 only✓

QUESTION 25 / 25

A 2070-ATC must report the time of day to the controller application. Which clock source is most commonly used for synchronization in a coordinated system today?

Choose one answer below.

AGPS-disciplined time receiver or NTP✓BAM/FM radio time signal✓CLocal oscillator only with no external sync✓DMechanical wind-up clock✓