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IMSA Traffic Signal Technician Level
II. All questions with verified
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Q.A traffic cycle / ( cycle length ) definition is? Is the total elapsed Time between the start of a specific display until the display comes up again. Example ( if the cycle starts at the beginning of a green display it will end when The same green display begins again after the red and yellow displays have been given. Q2 The acronym AWG stands for what? American wire gauge 3.Americans with disabilities act of 1990 ( ADA) is? Requirements ensuring equal opportunity for persons with disabilities and employment, state and local government services, Public accommodations, commercial facilities and transportation
Q The acronym ( CMS ) stands for what? Changeable message sign Q Changeable message sign is for what? Also known as variable message sign (VMS) and dynamic message sign (DMS) CMS are traffic control devices used for traffic warning, regulation, routing and management, and are designed to affect the behavior of motorist ( thus improve the flow of traffic) by providing real time highway related information Q What is a (Beacon)? A highway traffic signal with one or more signal sections that operates in a flashing mode. Q The acronym (ITS) stands for what? Answer Intelligent transportation systems Q intelligent transportation systems (ITS) what does it do? Answer Improves transportation safety and mobility and enhances productivity through the use of advanced information and communications technologies. ITS encompass a broad range wireless and wire line communications based information and electronics technologies (ITS)
What is a "platoon" A group of vehicles or pedestrians traveling together as a group, either voluntarily or involuntarily, because of traffic signal controls ,geometrical or other factors What is a "preemption control"? The transfer of normal operation of a traffic control signal to a special control mode of operation. What is a "Queue length "? Number of vehicles stopped or slowly moving in a line, where the movement of each vehicle is constrained by that of the lead vehicle What is a "signal warrant? A threshold condition that, if found to be satisfied as part of an engineering study, shall results in analysis of other traffic conditions or factors to determine whether a traffic control signal or other equipment is justified Which certification has level II and Level III? Traffic signal level II bench Traffic signal level II construction Traffic signal level II design Traffic signal level II field
Traffic signal level III Bench Traffic signal level III Electrician (field) (Traffic signal phase )is? Specific assigned timing function in the traffic signal controller. Are phases numbered 1 -8? True or false? True Even number phases are typically assigned to what movements? Through movements Phases 2-6 are assigned to? Major streets through movements Odd numbers ( 1,3,5,7) phases are assigned to what? Left turn phases
What are the two typically ( ring ) that a traffic controller have? "Single-ring" or "dual ring" What are other ( rings ) that are rarely used? And when are these types of rings used for? 3 or 4 rings & (used for two or more separate intersections are controlled by a single controller) What is a ( barrier)? Is a boundary point in the preferred sequence. Barrier that separates something so it won't have in the same time. How many (barriers) does a "dual ring controller" have? Two , one for leaving the MAJOR street and one for leaving the MINOR street. _______ ensure that green indications will not be given to conflicting movement at the intersection at the same time. Barriers What is a ( concurrent phase)?
Are movements that happen at the same time because do not conflict ( collide) with one another. Example of a ( concurrent phase ) A Through movement and a adjacent left turn movement can move on the same time. What is a (sequential phase)? Cannot happen at the same time because they conflict with one another ( collide) In a " sequential phases? How many movements can it have? Only one phase is served at a time Traffic signal industry has developed basic standards that provide common terms snd concept , but the most important thing is to have an understanding of your_______ Local agency standards What is (traffic signal timing)? The assignment of specific number of seconds for each interval of each controller timing function.
Most agencies set a standard for a minimum green initial green time. For a left turn face. How long should that minimum green be displayed for? 3 to 7 seconds Most agencies set a standard for a minimum green initial green time. For a minor street through phase. How long should that minimum green be displayed for? 5 to 15 seconds Most agencies set a standard for a minimum green initial green time. For a major street through phase. How long should that minimum green be displayed for? 15 to 25 seconds The common meaning for a passage time/ extension time/ gap extension is? Is the amount of time when a conflicting call is present that the controller will continue to Display a green light after the last vehicle has been detected What is the concept of a "passage time" and "extension time"? Making the time long enough for a vehicle leaving the advance loop to get to a point where It will continue through the intersection if the light turns yellow "Gap extension" concept is?
Making the time equal to the length of time between vehicles that is high enough so that the green time is no longer being used in thus it would be better to go to the next phase Maximum green time is? The highest amount of time that the green light can be displayed when a Conflicting call is present How is "maximum green times "for the various phases of the controller calculated? It's based on traffic volumes The maximum times can vary during the different portions for a typical day, specially if the controller as part of an area wide coordinated traffic signal system.. is this passage true or false? True Yello change interval does what? It alerts drivers that the green display has ended and that the right-of-way will be changing.
A "pedestrian head "at a intersection gives the pedestrian what information? The time they need to safely cross the street Pedestrian timings include both ________ & _______________? Walk interval and Pedestrian change interval. What is a "walk interval"? The amount of time that is given to the pedestrian that is using the crosswalk to get to the other side of the crosswalk safely. ( it's not related to the time needed to cross the stree) The MUTCD recommends _____ for the " walk interval " but allows the use of walk intervals as short of ______ seconds? 7 seconds and 4 seconds During the " walk interval" , the " pedestrian signal head" displays what symbol? Steady walking person symbol during the walking interval.
" pedestrian clearance time" should be sufficient to allow a pedestrian crossing in the crosswalk at the end of the WALKING PERSON symbol to travel at walking speed of? 3.5 feet per second "Pedestrian clearance time" provides what? enough time for a pedestrian who just enter the crosswalk to reach a safe location at the other end of the crosswalk before a green indication is displayed for other traffic. A pedestrian change interval consisting steps are?
- UPRAISED HAND (symbolizing Don't Walk! ) signal indication shall begin immediately following the WALKING PEROSN (symbolizing walk) signal indication. Following the pedestrian change interval. Consisting of a (steady UPRAISED HAND) symbolizing don't walk signal indication shall be displayed for at least 3 second prior to the release of any coming traffic. A " buffer interval consisting of a? Steady ( UPRAISED HAND ) symbolizing don't walk! The sum of the time of the _______ and _______ shall not be less than the calculated "pedestrian clearance time" Pedestrian change interval and the buffer interval
"Pedestrian recall" is? Is set for a phase, the controller treat the phase as having a pedestrian call at all times. What "recall "will cause the controller to show a walk signal and pedestrian change interval to the phase every cycle. "Pedestrian recall" Traffic signal coordination timing is? Providing a efficient flow of traffic through multiple intersections, the reduction of stops and delays. What are the basic terms that help "traffic signal coordination"? Cycle length , split , offset , yield point, force-off For coordination to happen, all of the coordinated traffic signals along the street must have the??? Same "cycle length" during the same time of the day
The common cycle length at each intersection in the system can change throughout the day why? To handle different traffic Volumes, with higher cycle lengths Generally being used during peak hours and shorter cycle lengths being used during off-peak hours What "split " in traffic signal coronation timing? Is the number of seconds given to each phase at the intersection What is the "offset" of a cycle? The number of seconds from the common Signal cycle point, to another point. What are some examples for a "offset point "? End of the green indication. End of mainline green, beginning of mainline green, first green The assessment of different_______ at the various intersections is what causes the intersection to work together. "Offset" What is another point in the cycle of a coordinated traffic signal controller where the major street phase is allowed to end?
Is a distributed processor system with control logic provided at three levels The closed loop system is a distributed processor system with control logic provided at three levels. Those Three levels are: The local controller., the on-street master and the central computer. What are the disadvantages of a "closed loop system"? The inability to easily switch local controllers to a different on-street master in response to varying traffic conditions. What is a "central computer system "? a computer at a centralized location makes decisions and communicates to each individual local controller in the system. The standard traffic signal controller receives commands from where and what happens if communication is lost? Receives commands from central computer, if communication is lost the local controller is forced to revert to its backup plan Communications in Closer loop system typically consist of what?
A twisted repair copper cable or fiber optic cable between local controllers and on street masters and than either telephone modems back to the central computer or I some cases cable throughout the system. "Hardwire interconnect" is? The common term for a cable that transmits data between controllers and on street masters or between controllers and central computers Copper cables are terminated in local controller cabinets to an _______? "Interface panel" Standard traffic signal controller receives commands from the? "Center computer system What is another option that can be used for transmitting and receiving signal system data? Telephone communications "Telephone system" is for what signal system communications
