High-Traffic Areas - answerHigh-volume streets, such as arterials. Typically wide and
have multiple lanes of travel.
Low-Traffic Areas - answerLow-volume streets such as local streets or collector streets.
Typically narrow and have single lanes of travel.
Insulated Hand Tools - answerTools with insulated handles, designed to protect from
electric shock when working with live electricity.
Insulated Mats/Blankets - answerSafe place to stand when working on electric systrems
Circuit Breaker Finders - answerTool that helps locate the appropriate circuit breaker or
fuse that controls the electrical supply to the area.
Conductors - answerMaterials that conduct electricity
Ex. Most metals
Insulators - answerMaterials that do not conduct electricity
EX. plastic, rubber, glass, ceramic
Understanding electricity - answerElectricity is similar as water flowing through pipes
Voltage is like water pressure.
Current is like amount of water.
Resistance is like the size of the pipe.
Ohm's Law - answerE = I x R
E = Voltage(Electromotive Force) (Volts)
I = Current(Intensity) (Amps)
R = Resistance (Ohms)
120 VAC/ 24 VDC - answerTypical voltages used in traffic signal circuits
Alternating Current - answerThe electrons flow in a switching direction going forward
and backwards. In a power grid usually 120 Volts at 60 cycles per second(Hertz)
EX.Powers homes, businesses, factories
Direct Current - answerelectrons flow in one direction
5, 12, 24 Volts usually
, EX. Batteries, power supplies
Bonding and grounding - answerJoining metallic parts and using them to provide an
electrically conductive path to the ground
Phases - answerThrough phases are typically even numbered and left turn phases are
odd numbered. Phases 1- 2- 5- 6 are the main street, while 3 -4 - 7 -8 are the side
street
Concurrent group - answerphases that are grouped on the same street. phases usually
turn on with the the others in their group. divided by barrier, e.g main street/ side street
Ring - answeridentifies phases that may operate one after another. organizing
conflicting phases such as a left turn not being on while through is on the opposite way.
Barrier - answerSeparates opposing phases to avoid conflicting movements at the same
time. Also helps in rings relationship
Protected Phases - answerProvide exclusive right-of-way to a specific movement,
allowing passage with no conflicting traffic
Permissive Phases - answerAllow movement to proceed with caution when there is a
gap in conflicting traffic. Usually yielding or giving right of way to crossing traffic
Calculating signal intervals - answerTurning movement counts - data on traffic volume
Signal phasing- data on terrain
Minimum green time- time to clear intersection
Pedestrian clear time
Yellow & All-Red Intervals
Coordination & Optimization
Split - answerAllocation of time within a single cycle for a specific movement or phase. it
represent the duration or percentage
Offset - answertime difference between the initiation of signal phases or intersections
along a corridor. Effective offset can help reduce stops, improve travel times, enhance
fuel efficiency
Lead Left-Turns - answerprotected left-turn served prior to the complementary through
movement. most common
Lag Left-Turns - answerProtected left turn served after the complementary through
movement. most used in coordinated systems with closely spaced lag left turn
intersections such as diamond interchanges
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller julianah420. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $15.49. You're not tied to anything after your purchase.