IMSA Traffic Signal Tech 1 Study Guide 2024

Describe the significance of Garrett Morgans contribution to traffic signal development and how it impacted modern traffic systems

Developed a three-position traffic signal adding a 'warning' phase to reduce collisions.

"What are the two key purposes of traffic signal systems?"

Traffic regulation and flow optimization

OSHA stands for what?

Occupational Safety and Health Administration

SDS sheets provide what type of information?

safety data sheets for chemicals

Which of the following is NOT considered part of the PPE for a Traffic Signal Technician?

Sneakers

What is the maximum AC voltage that Class 0 electrical gloves can handle?

1,000 volts

What is the minimum OSHA-mandate clearance from overhead power lines?

10 feet

Which organization is responsible for publishing the National Electrical Code (NEC)

NFPA

In Ohm's Law, what does the formula E = I x R represents?

Voltage = Current x Resistance

Which of the following is NOT a type of traffic signal warrant as per MUTCD

Vehicle Age

What is the primary purpose of "fully-actuated" traffic signal?

To respond to real-time traffic demands

How often is it recommended for a Conflict Monitor Unit (CMU) to be tested and recertified?

Every Year

In electrical terms, what does `current 'refer to?

Water Flow

The NEC handbook is published by?

the National Fire Protection Association, which is responsible for developing and updating the NEC

Which document determines the hierarchy of utilities on a utility pole?

NESC

Part four of the __________ determines all the guidance for traffic signals

MUTCD

What does OSHA stand for?

Occupational Safety and Health Administration

Who published the NEC?

NFPA

Legal Liability : Negligence

failure to exercise a reasonable standard of care expected under the circumstances, leading to an increased risk of accidents and harms.

Tort Liability

This would be a non-criminal act or failure to act by one party that leads to harm or damages to another party

what would be failure to use exact care in one's actions?

Negligence

A technician was sent out to an intersection to replace a broken traffic signal head. When he arrived on the scene, he realizes he does not have the proper hardware to reinstall the fixture. He only secures the fixture with two screws and leaves for the evening and forgets to come back to complete the repair. The fixture falls on a car and causes a serious accident with injuries. This is a what?

Tort Liability

Electrical safety gloves

are classified by the level of voltage protection they provide and are subject to strict standards. In the United States, these standards are set by the American Society for Testing and Materials (ASTM)

OSHA mandates that you MUST maintain a minimum of ___ foot of clearance from overhead power lines?

10 feet

Look for _____ on poles as overhead utilities may transition to become underground utilities

Risers

Locate Color Red

Electrical Power Lines

Locate Color yellow

Natural Gas, Steam, Petroleum, oil lines

Locate Color Blue

Portable water lines

Locate Color Green

Sanitary sewer and Storm drain lines

Locate Color orange

Communication lines - phones, cable tv, fiber optic

Locate color pink

Temporary surveying markings

Locate Color purple

chilled water, reclaimed water, irrigation and slurry lines

Locate color white

proposed excavation

Locate color Not specified

Military and Private underground Facilities

Which formula is part of Ohm's Law?

E = I x R

OSHA mandates that you MUST maintain a minimum of ____ feet clearance from overhead power lines?

10 feet

Individuals, using arial lift trucks should_________?

Be properly trained, inspect their vehicles, wear appropriate fall protection equipment.

what does bonding and grounding" mean?

Bond everything to the same electrical potential

What does a TDR/OTDR do?

measures anomalies in a wire or optical fiber

Which piece of test equipment would you use to measure the insulation resistance of your conductor?

A megohmmeter

Which piece of equipment would you use to certify your conflict monitor's ?

A MMU/CMU Tester

Which piece of test equipment is commonly used to measure voltage, resistance, and current?

A multimeter

Everything turns into molten metal upwards of _____ degrees (arc flash)

35,000 degrees

`What type of power do traffic signals typically operate on?

120 VAC

What is the DC - (direct currents) typical voltage used in electronics?

Typical voltages used in electronics are 5 Volts, 12 Volts, and 24 Volts.

What is AC (Alternating Current) typical volts and how many cycles per second?

It is typically 120 volts and alternates at 60 cycles per second (60 Hertz)

What is bonding?

Article 100 of the NEC defines bonded (bonding) as "connected to establish electrical continuity and conductivity."

What is one thing that all detection devices have in common?

They send an input to the controller

Parallel Circuit

voltage remains the same, power adds up

series circuit

current remains the same, resistance adds up, power adds up

combination circuit

power adds up

Which condition would indicate the need to replace a pole or mast arm?

Dents

What is the most common material used in electrical wiring?

Copper

which of the following is NOT a commonly used hand tool for a traffic signal technician?

Power Drill

Vehicle phases are also assigned numbers, typically _ thru _

1 thru 8

A Ring consist of:

A ring consists of two or more sequentially timed and individually selected conflicting phases so arranged as to occur in an established order

A Barrier is?

A reference point in the preferred sequence of a multi-ring controller in which all rings are interlocked

A ______ phase can be on with another phase in its concurrent group.

concurrent phase

Leading phases are defined as -

are defined as the first phase(s) serviced once you cross a barrier

Leading / Lagging are specifically referred to?

Leading / Lagging are specifically referred to the left turn movements

Lead Lag left turns

During this operation, leading left-turn phasing and lagging left-turn phasing are provided on opposing approaches of the same street

Protected Phase:

Protected phases provide exclusive right-of-way to a specific movement, allowing vehicles or pedestrians to proceed with no conflicting traffic.

Permissive Phases

Permissive phases allow a movement to proceed with caution when there is a gap in conflicting traffic. These phases typically involve yielding or giving right-of-way to opposing or crossing traffic.

The three most common recalls are -

Minimum, Maximum, Pedestrian recall

Yello Clearance interval -

will never be anything less than 3.0 seconds as per the FHWA, 5.3.2

Cycle Length

represents the duration required for the signal to go through all of its programmed phases

Cycle splits

A "split", as defined by NEMA refers to the segment of the cycle length allocated to each phase that MAY occur

What best describes a barrier?

An interlock in a multi-ring controller

A ________________ will terminate after its controlling phase has terminated which may operate as either a _____________ or _____________ phase

A timed overlap will terminate after its controlling phase has terminated which may operate as either a lead or lag phase

An intersection that operates with vehicle detection on all approaches is _____________.

An intersection that operates with vehicle detection on all approaches is fully actuated

A movement of traffic that is controlled by two or more phases is known as __________________.

A movement of traffic that is controlled by two or more phases is known as parent child overlap

A complete sequence of signal indications is better known as a:

Cycle length

National Electrical Manufacturers Association created the first traffic signal standards in 1976

NEMA (national manufacturers association)

Conflict Monitor Units (CMU) - exist in

TS-1 & Type 170 cabinets

MMU's - exist in

TS-2 cabinets

What is the role of the conflict monitor unit (CMU)?

to monitor the cabinets operating conditions for faults

A serial interface unit (SIU) is used in:

the ATC cabinets

Communication Protocols:

The SIU supports specific communication protocols, such as NTCIP (National Transportation Communications for ITS Protocol)

Inputs and Outputs:

It communicates this through serial bus #1 (SB1) and serial bus #2 (SB2).

The primary function of a load switch is to receive

the 0/24 VDC input control signals from the controller and output a 120 VAC signal to the appropriate signal indications in the field

High-density switch packs:

These high-density switch packs are only used in the ATCC cabinets

The thermostat should be within a safe temperature range of ___ degrees

85-165 degrees

What cabinet device acts as an interface device between the controller and the field terminals?

Load Switch

What cabinet device switches the traffic signals between a flash state and normal operation?

Flash Transfer Relay

What cabinet device facilitates communications between the field terminals, the detection devices and the MMU?

Bus Interface Unit

The MUTCD states that the flashing output on a flasher must be _____ per minute?

50-60

What unit is described as the brain of the traffic signal system?

Controller

The NEC mandates that multi-conductor cables cannot fill more that ___ of a conduit.

40%

Types of conduit -

GRC,IMC,EMT

PVC (polyvinyl chloride)

The higher the schedule number, the thicker the wall

HDPE (high density polyethylene)

The higher the SDR number the thinner the wall

cohesive soil

soils that have a high clay content. Wet soils tend to stick together and maintain the shape of the drilled shaft. Cohesive soils compact very well

cohesionless soils

- soils that tend to be granular in nature; I.E., sand & gravel. These soils have a hard time holding the shape of the drilled shaft and tend to sluff off. Cohesionless soils are harder to maintain compaction

Tier Rating

The tier rating is represented by a number times 1000. For example, a tier 8 box is rated for 8,000 pounds

PTZ cameras

Pan-Tilt-Zoom (dome cameras)

how does someone identify a particular device on a network?

IP address

What does an IP address look like?

192.0.128.64 (numbers and periods)

What does an Mac address look like

"D2-FF-23-00-C3-A1" (looking for dash, letters, numbers)

When installing a traffic control cabinet, which of the following should you NOT do?

Secure cabinet facing the intersection, so technician's back is to the intersection

What does PTZ stand for?

Pan, tilt, zoom