T3 Webinar:

Technical Deployment Review of the ITS Cabinet Standard

Webinar File(s)

• PowerPoint® presentation used in webinar
• Text version of PowerPoint presentation used in webinar
• Transcript for entire Webinar (presentation, question and answer)

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Text version of the PowerPoint presentation. Description of image or images on a slide contained in brackets.

Slide 1: Title

Technical Deployment Review of the ITS Cabinet Standard

Slide 2: Host and Presenter

THE FED
Edward Fok
FHWA Resource Center — Operations Technical Service Team

THE EXPERT (PRESENTER)
Ron Johnson
Houston TranStar Quality Assurance Engineer
Co-Chair of the ITS Cabinet Standards Working Group

Slide 3: Presentation Overview

• This presentation will show how an existing ITS Standard is actually deployed in the field
• Meant to be rich in technical contents
• Intended audience are field engineering personnel
• Facilitated in part by FHWA's ITS Standards field support team
  • Encourage better understanding of the Standards
  • Help developers create better Standards

Slide 4: ITS Cabinet Standard

• Standard Development Organization
  • Institute of Transportation Engineers
  • NEMA
  • AASHTO
• One of Three Advanced Traffic Controller family of Standards
  • ATC Controller
  • ATC API
• Version
  • 1.02.17b
• Currently Deployed by:
  • Houston TranStar (Harris County)
  • Farmer's Branch (Dallas)

Slide 5: Cabinet Types

• NEMA ,170 and ITS Cabinets are distinct in size shape and form
• NEMA Cabinets fall in three sizes M, P and R
• Typically NEMA enclosures are equipped with shelves to mount the equipment
• 170 cabinets are distinct in that they use 19inch rack system to house the equipment
• ITS cabinet is designed to accommodate equipment designed for both 170 and NEMA Cabinets
• The city of Houston uses 170 Cabinets as well as NEMA enclosures, most common being the P-sized Cabinet

Slide 6: Major Elements

• 3 different housing types
• Modular components and Buses
• Cage assembly
  1. "J" Panel
  2. Shelve Assemblies
  3. Service Panel Assembly
  4. Power Distribution Assemblies
  5. Input and Output Assemblies
  6. Serial Communication Assemblies
  7. Cabinet Monitoring Assemblies

[An image of the cage assembly appears.]

Slide 7: Housing #1 and Cage

[A graphic shows the chematic of Housing #1 and cage. Show from front (2-D) and angle (3-D). (Page 165 and 168 of the standard document.)]

Slide 8: Housing #1

[Slides displays two pictures of Housing #1: one from the front and one from the back.]

Slide 9: Housing #2 and Cage

[A schematic of Housing #2 and cage appear. Show from front (2-D) and angle (3-D). (Page 165 and 168 of the standard document.)]

Slide 10: Housing #2

[Two pictures of Housing #2 appear: one from the front and one from the back.]

Slide 11: Housing #3 and Cage

Contain two Housing #1 Cage Assemblies

[Schematic of Housing #3 and cage appear. Show from front (2-D) and angle (3-D). (Page 166 and 168 of the standard document.)]

Slide 12: Housing #3

[Slide displays a picture of Housing #3 installed in the field. The cabinet's doors are open. ]

Slide 13: ITS Cabinet System Architecture

[Slide displays a network symbolized by boxes grouped from top to bottom of the slide. From top to bottom: Controller, Input Assembly (SIU), Input Assembly (SIU), Power Distribution Assembly (CMU), Output Assembly (AMU/SIU), Output Assembly (AMU/SIU). Serial Bus 1 & 2, represented by a red line, connects all boxes. Serial Bus 3, represented by a blue line, connects the Power Distribution Assembly box, from the CMU, to both Output Assembly boxes through the AMU. ]

Slide 14: "J" Panels

• Simple side panels made of Aluminum with multiple holes and slots to support various parts and component
• The type of "J" panels needed are specified by the cage assembly required by each housing

[Slide displays a schematic and a picture of the "J" Panel for Cage 1 Housings 1 & 3 and Cage 2 Housing 2. (Page 173-174 of the standard document.)]

Slide 15: Bus and Shelve Assembly Details

• The bus assembly is hooked on the "J" panel for rear support and attached to the EIA Rail for front support with screws through the slots
• The shelve assembly is mounted on the "J" panel with bolts in four places for support

[Slide displays a schematic of the bus and shelve assembly details. (Page 199 of the standard document.)]

Slide 16: Service Panel Assembly Details

[Slide displays a schematic and a picture of the Service Panel Assembly. (Page 175 of the standard document.)]

Slide 17: Raw/Clean AC Power Assemblies

• Provide Raw AC for signaling on Output Assemblies
• Contains the control of the FTR's
• Provides Flasher Power to the load switches during flashing operation
• 120 VAC filtered (Clean) power outlets for cabinet equipment
• An additional "L" Assembly has been added to make better use of the 14 Pack Output Assembly

[Slide displays a schematic and a picture of the Raw/Clean AC Power Assemblies. (Page 179-180 of the standard document.)]

Slide 18: DC Power and Communications Assembly

• The DC Power and extension bus provide power for the standard assemblies as well as other optional devices that are used within the ITS Cabinet Platform. One example would be Ethernet switches that are used for our communications interface.

[Slide displays a picture of the DC Power and Serial Communications Bus Assembly. (Page 183 of the standard document.)]

Slide 19: DC Power and Serial Communications Bus Assembly

[Slide displays a picture of the DC Power and Serial Communications Bus Assembly. ]

Slide 20: DC Power and Communications Assembly

• The DC Power and Communications Assembly provides a unique interface for the Serial Busses 1 and 2 for interface between the Controller and the Serial Interface Modules.

[Slide displays a schematic and image of the DC Power and Communications Assembly. (Page 184 of the standard document.)]

Slide 21: Power Distribution Assembly (PDA)

• Provides clean power distribution to the Power Supplies and various devices.
• Houses 2 Flashers Control relays, load resistors for the Optical interface and power contactor for the signals. The CMU (Cabinet Monitor Unit) resides in the PDA and monitors all the control signals from the police panel and flashers.
• House two low voltage DC Power Supplies 24VDC and 12VDC slide out assemblies.
• "L" version uses a rack mounted Power Supply functionally the same as the plug in versions. In Housing 1 and 2 a single 24VDC Power Supply is needed. Housing 3 uses an additional 12VDC Power Supply for power to the Input Detectors.

Slide 22: Power Distribution Assembly

[Slide displays a schematic of the Power Distribution Assembly from the perspective of the front view of the cabinet. (Page 185 of the standard document.)]

Slide 23: Power Distribution Assembly

[Slide displays a picture of the Power Distribution Assembly from the front view of the cabinet. The picture shows the location of the 12-VDC Supply and 24-VDC Supply.]

Slide 24: "L" Power Distribution Assembly

The "L" Power Distribution Assembly is mounted at the upper rear on Housing #1 & #3 cages, and at the lower front on the Housing #2 cage.

[Slide displays a schematic of the "L" Power Distribution Assembly mounted Upper Rear on Housing 1 & 3 cages and Lower Front on Housing 2. (Page 186 of the standard document.)]

Slide 25: "L" Power Distribution Assembly

[Slide displays a picture of the "L" Power Distribution Assembly.]

Slide 26: Power Distribution Assembly

[Slide displays a schematic of the Power Distribution Assembly fron the perspective of the rear of the cabinet. (Page 187 of the standard document.)]

Slide 27: Power Distribution Assembly

[Slide displays a picture of the Power Distribution Assembly fron the perspective of the rear of the cabinet.]

Slide 28: PDA Connections

[Slide displays two pictures: one of a service connector, the other of a raw power connector.]

Slide 29: Cabinet Electrical

[Slide displays a schematic cabinet electrical power distribution. (Based on page 188 of the standard document.)]

Slide 30: Cabinet Wiring Harness

• The only wiring done within the Housing is the wiring associated with the CC Connector
• This harness is the same for all types of ITS Cabinet Housing
• This includes:
  • Fan and light control
  • Flash
  • Signals On/Off
  • Manual Control and Interval Advance
  • Manual Stop Time Switch input

[Slide displays a schematic of the CC (Cabinet) Connector. (Page 181-182 of the standard document.)]

Slide 31: Wiring Harness Schematic

[Slide displays a schematic of the Wiring Harness. (Page 211 of the standard document.)]

Slide 32: Cabinet Input Assembly

• Communicate either via contact Closure or Serial data strings via Serial Bus #1
• Smart Detectors can be used to send
  • Vehicle Classification data
  • Automated Vehicle Location Data/Location data
  • Speed Information data
• 100% Compatible with NEMA input detector cards
• The entire input assembly with field terminals is a unitary modular unit

Slide 33: Input Assembly Front and Rear View

[Slide displays two schematics of the Input Assembly: one from the front, the other from the rear. (Page 203-204 of the standard document.)]

Slide 34: Connector Details

[Slide displays two pictures: one of the Input/Output Assembly that shows the location of the CDC, the Serial Bus Connector, and the Test Connector. The other picture is of the Removable Field Termination Connectors.]

Slide 35: Four Input Files — Houston
Housing 3

[Slide displays a picture of the four Input Files in Houston's Housing 3. It shows the SIU Connector and 12 slots for two-channel devices. ]

Slide 36: Input File (Rear) With Removable Connectors

[Slide displays a picture, from the rear, of the Input File with Removable Connectors. ]

Slide 37: Output Assembly Features

• Two Versions 6 Position and 14 Position
• Provides Cabinet Flash, FTR and Flash Jumpers
• System Bus Address supports up to 32 load switches
• The entire output assembly with field terminals is a unitary modular unit
• The assembly is pre-wired for parallel or serial inputs
• The Field Terminals are wired to the AMU for serial monitoring and AC protection
• Includes current monitoring if desired

Slide 38: 6 Position (6 Pack) Output File

[Slide displays two schematics of the 6 Position (6 Pack) Output File, one from the front and one from the rear. (Page 191-192 of the standard document.)]

Slide 39: 6 Position (6 Pack) Output File

[Slide displays two pictures of the 6 Position (6 Pack) Output File, one from the front and one from the rear. The pictures shows the location of the SIU and AMU.]

Slide 40: 14 Position (14 Pack) Output Assembly

[Slide displays a front-view schematic of the 14 Position (14 Pack) Output Assembly File. (Page 192 of the standard document.)]

Slide 41: 14 Position (14 Pack) Output Assembly

[Slide displays a rear-view schematic of the 14 Position (14 Pack) Output Assembly File. (Page 192 of the standard document.)]

Slide 42: Rear View

[Slide displays a rear-view picture of the 14 Position (14 Pack) Output Assembly File. ]

Slide 43: Output Socket Detail

[Slide displays a picture of the Output Socket Detail. The picture shows the location of the Address Block, the Field Wiring Connector, the FTR Socket, and Lightening Protection. ]

Slide 44: Output File Connections

[Slide displays pictures of Output File Connections. Shown are the DC Power Connector, the AC Field Connector, the Lightening Protector, the AC Connector Clean Power, and the Signals-AC Connector.]

Slide 45: Cabinet Serial Comm. Network

[Slide displays the Cabinet Serial Communications Network symbolized by a network of boxes grouped from top to bottom of the slide. From top to bottom: Controller, Input Assembly (SIU), Input Assembly (SIU), Power Distribution Assembly (CMU), 14 Pack Output Assembly (AMU/SIU), 6 Pack Output Assembly (AMU/SIU). Serial Bus 1 & 2, represented by a red line, connects all boxes. Serial Bus 3, represented by a blue line, connects the Power Distribution Assembly box, from the CMU, to both Out Assembly boxes through the AMU. ]

Slide 46: Cabinet Serial Communication System

• Similar to the NEMA TS-2 using Synchronous Data Link Control (SDLC) protocol
• Serial interface unit (SIU) is the cabinet communications and control unit
  
  SERIAL BUS 1
  • command / response, distributed processing of outputs and status/detection or status of inputs
  SERIAL BUS 2
  • Collects preprocessed data from sensors or modular NTCIP devices
  SERIAL BUS 3
  • dedicated to monitor cabinet systems

[Slide displays the Cabinet Serial Communications Network symbolized by a network of boxes grouped from top to bottom of the slide. From top to bottom: Controller, Input Assembly (SIU), Input Assembly (SIU), Power Distribution Assembly (CMU), 14 Pack Output Assembly (AMU/SIU), 6 Pack Output Assembly (AMU/SIU). Serial Bus 1 & 2, represented by a red line, connects all boxes. Serial Bus 3, represented by a blue line, connects the Power Distribution Assembly box, from the CMU, to both Output Assembly boxes through the AMU.]

Slide 47: Serial Bus #1

• "Real-time" communications from Controller to I/O
• 614 kbps communications speed, SDLC frames
• Command / response protocol with CRC and timeouts
• Controller "talks" to all devices in cabinet at once
• Peripheral device "listens" for its address and responds
• Normally used with Serial Interface Units (SIU)
• Same protocol as Field I/O (FIO), but at different addresses

Slide 48: Serial Bus #1

• Used for real time information required to operate the system
  • Highest Priority
  • Time Sensitive data exchanges
  • Connected to Controller, SIU and CMU
• Maximum speed 614 kbps

[Slide displays Serial Bus #1 Communication Network and how the bus connects to the Controller, Input Assembly (SIU), Input Assembly (SIU), Power Distribution Assembly (CMU), 14 Pack Output Assembly (AMU/SIU), 6 Pack Output Assembly (AMU/SIU). The image also shows that Serial Bus 3, represented by a blue line, connects the Power Distribution Assembly box, from the CMU, to both Output Assembly boxes through the AMU.]

Slide 49: Serial Bus #2

• SB2 located in same cabinet 25-pin "D" connector, CAT5
• Separate communications channel directly from controller to serial detectors for loop tuning, status, etc
• Used for long "conversational" messages without impacting I/O update performance
• Protocol differs with each vendor and hardware device
• Software driver comes with each hardware device and is installed on 2070 ATC, similar to PC device drivers
• Anticipates future serial detectors other ITS applications

Slide 50: Serial Bus #2

• Use for less critical information between the controller and SIU inputs and outputs
• For example returning vehicle counts, classification, other info requested by a central system
• Also for preprocessed data from detector devices or modular NTCIP devices
• Max speed of 614.4 kbps

[Slide displays Serial Bus #2 Communication Network and how the bus connects to the Controller, Input Assembly (SIU), Input Assembly (SIU), Power Distribution Assembly (CMU), 14 Pack Output Assembly (AMU/SIU), 6 Pack Output Assembly (AMU/SIU). The image also shows that Serial Bus 3, represented by a blue line, connects the Power Distribution Assembly box, from the CMU, to both Output Assembly boxes through the AMU. ]

Slide 51: Serial Bus #3

• Dedicated to communications between CMU and AMU
• Used to allow CMU to monitor
  • Voltages
  • Operating Conditions
  • Currents
• To determine actual switch pack conditions
• Operates at 153.6 kbps

[Slide displays a picture of Serial Bus #3. ]

Slide 52: Serial Bus #3

• Monitor system bus
• CMU / auxiliary monitor unit (AMU)
  • Driven by CMU via SDLC protocol
  • Communication uses EIA- 485 standard

[Slide displays Serial Bus #3 Communication Network and how the Serial Bus #1 and #2 connects to the Controller, Input Assembly (SIU), Input Assembly (SIU), Power Distribution Assembly (CMU), 14 Pack Output Assembly (AMU/SIU), 6 Pack Output Assembly (AMU/SIU). The image shows that Serial Bus 3, represented by a blue line, connects the Power Distribution Assembly box, from the CMU, to both Output Assembly boxes through the AMU. ]

Slide 53: Serial Interface Unit (SIU)

• SIU — Microprocessor based communications device
• Sends and receives SDLC data from SB #1 and SB #2

[Slide displays a picture of the Serial Interface Unit (SIU) and the location in the Cabinet. ]

Slide 54: Cabinet Monitoring System

• Provides a fail-safe mechanism for the entire collection of sub-assemblies
• Components Include
  • CMU — Conflict Monitor Unit
  • AMU — Auxiliary Monitor Unit
• Extremely flexible and expandable
• Allows for response to a conflict at a single intersection and not impact other intersections/ramps/etc operated by same controller

[Slide displays a diagram of the Cabinet Monitoring System and its location in the overall cabinet communications network. ]

Slide 55: Conflict Monitor Unit — CMU

• Housed in the PDA — Main processor of cabinet monitoring
• Monitors main cabinet functions
  • Cabinet power
  • Door status
  • Status of the Flasher
  • Communicates to other AMU
• Communicates via Serial Bus #1 to the controller and Serial Bus #3 to the AMU
• Controller asks for real time status and compares what it thinks it sent to load switches to what is actual happening

[Slide displays a picture of the Cabinet Monitor Unit (CMU). ]

Slide 56: Conflict Monitor Unit — CMU

• CMU is addressed so that multiple CMU can be accommodated within one cabinet (Multiple PDA's)
• Addressing is accomplished via the PDA rear programming jumpers
• Diode board has been replaced with a serial memory key.
  • Non Volatile computer memory
  • Stores configuration data for the monitor and replaces the diode board
  • During start up sends configuration to controller for checking

[Slide displays a picture of four serial memory keys.]

Slide 57: CMU Block Diagram

[Slide displays the CMU Block Diagram.]

Slide 58: Auxiliary Monitor Unit (AMU)

[Slide displays a picture of the Auxiliary Monitor Unit (AMU).]

• Housed in each output assembly
• Monitors the outputs (Voltages and Currents) of the switch packs and reports this status to the CMU
• This allows for flexibility in cabinets
• Four units are accommodated in this system
• Normally these devices are all contained in the same cabinet
• Sends Field status to CMU

Slide 59: AMU Block Diagram

[Slide displays the AMU Block Diagram.]

Slide 60: Putting it All Together

[Schematic of Cabinets #1 and #3.]

Slide 61: Field Installation — Housing #1

[Slide displays two pictures of field installation of Housing #1-one from the front and one from the back. ]

Slide 62: Field Installation — Housing #3

[Slide displays three pictures of field installation of Housing #3. One picture of a technician wiring and installing the housing to its base; another picture of three technicians maneuvering the housing onto its base; a last picture of the housing completely installed. ]

Slide 63: Ongoing/Future Initiatives

• High Occupancy Vehicle Control
• Traffic Incident Management
• Remote device interrogation and diagnosis
• Conversion of parallel circuit to pure serial circuit

Slide 64: Lessons Learned

• Specification can indeed become reality
• Housing 3 has been the standard for Harris County since it directly fits on a NEMA "P" foundation allowing deployment with the least cost, since we are able to use existing wiring, conduit and pull boxes and foundation.
• The modular construction of the assemblies will allow an agency to buy equipment to a base standard then do custom design as needed.
• In addition to modularity the Conflict Monitoring system is the most comprehensive and versatile hardware yet produced.

Slide 65: Questions?

• Session transcripts:
  • Email : edward.fok@fhwa.dot.dov
  • Use subject heading: ITS cabinet T3 transcript
    • Will contain slides and Q&A
    • Available in about two weeks
    • Do not submit follow up question with this subject heading
• Standards document and related questions: www.ite.org
• TranStar related questions: RJOHNS8@houstontranstar.org

Slide 66: Next T3 Webinar

• April 5th 13:00 – 14:30 EDT
• Topic: "ITS System Engineering (SE) for ITS: Using FHWA's New SE Handbook" (repeat session)
• Register at:
  • http://www.pcb.its.dot.gov/t3/s070913_se_guide.asp
    (registration closed—link disabled)
  • Clicking on T3 link on ITS PCB homepage at: http://www.pcb.its.dot.gov
• All T3 webinars are free of charge

Slidse 67 – 69: Acronyms

AASHTO	American Association of State Highway Transportation Officials	CC	Cabinet Connector
AC	Alternating Current	CDC	Cabinet Distribution Connector
ACCP	AC Clean Power	CMU	Conflict Monitoring Unit
ACP	AC Raw Power	COMM	Communication
AMU	Auxiliary Monitoring Unit	CRC	Cyclic Redundance Check
API	Application Program Interface	DC	Direct Current
ATC	Advance Transportation Controller	DCP	DC Power
CAT5	Category 5	EIA	Electronic Industries Alliance
EQ	Equipment	GFI	Ground Fault Interrupt
FHWA	Federal Highway Administration	GND	Ground
FIO	Field Input/Output	I/O	Input/Output
FP	Flash Program "Block"	IA	Interval Advance
FT	Field Termination	ISO	International Organization for Standardization
FTR	Flash Transfer Relay	ITS	Intelligent Transportation System
FUC	Flash Unit 1 and 2	KBPS	kilo bits per second
G	Green	MCE	Manual Control Enable
NEMA	National Electrical Manufacturer Association	TBS	Terminal Block "Service"
NTCIP	National Telecommunication for ITS Protocol	TR	Transfer Relay
PDA	Power Distribution Assembly	TRANSTAR	Harris County transportation operation agency
R	Red	VAC	AC Voltage
RC	Resistor Capacitor Filter	VDC	DC Voltage
SB	Serial Bus	Y	Yellow
SDLC	Synchronous Data Link Control
SIU	Serial Interface Unit

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