
D4 Traffic Signal Controller
Feature Summary (Version 1.4o)
General Controller
Features
- 16 phases
- Three maximum times per phase with dynamic max
operation
- Minimum, maximum, soft recall modes
- Early and delayed “Walk” timing
- Conditional service during free and
coordination, with conditional service minimum green time
- Manual control operation with selectable call,
omit, and protected pedestrian clearance phases
- Per phase preempt timing
- 4 rings (Single intersection or two independent
intersections)
- 16 timed overlaps
- Vehicle and pedestrian movement for each
overlap
- Actuated pedestrian movements
- Early and delayed “Walk” timing
- Pedestrian overlap rest-in-walk across multiple
phases
- Per overlap preempt timing
- 8 transit phases
- Two and three section signal head controls for
light rail vehicles
- Advanced warning sign control per transit phase
- Recall or actuated operation
- Normal or priority service
Detector Features
- 64 vehicle detectors
- Programmable call and extend phases
- Extend and delay timing
- Stop bar disconnect mode with carryover
(extend) timer
- Detector cross-switching
- No presence and max fail detector diagnostics
(disabled by TOD)
- 16 queue detectors
- Detects traffic backups
- Capable of selecting alternate coordination
patterns, selecting alternate maximum green times, or calling a preempt
- Advanced green to clear vehicle movements prior
to transit vehicle arrival
- 16 pedestrian detectors
- Programmable calls for pedestrian and vehicle
phases
- Pedestrian cascade mode (sequential calling of
two pedestrian movements)
- 8 transit detectors
- Programmable calls for transit and vehicle
phases
- Extend and delay timing
- Travel time delay
- Alternate travel times by TOD
- Adaptive arrival time adjustment
- 32 remote transit detectors
- Calls received by transit detectors at other
intersections (on peer-to-peer Ethernet network)
- Travel time delay
- Alternate travel times by TOD
- Adaptive arrival time adjustment
Coordination Features
- 32 coordination patterns
- Cycle time and three offsets per pattern
- Flexible per phase split expansion and
shrinking during transition
- Fixed or floating force-offs (per phase)
- Automatic permissive calculations
- Single-band or multi-band permissive modes
with permissive limit timer
- Three pedestrian permissive modes
- Programmable recalls and omits active during
each pattern
- Actuated coordinated phases can gap-out early
and distribute unused time to movements with greater demand
- Selectable reservice
phases (a.k.a. “fully actuated coordination”)
- Multiple interconnect modes
- Time based scheduler
- Central system command (over twisted pair or
Ethernet connection)
- 120 volt interconnect cable
- Master controller mode
- Controller can operate as a twisted pair,
Ethernet, or 120 volt cable master in the absence of a central management
system
Preemption Features
- 10 prioritized preempts
- Two track clearance states, dwell state, and
exit state per preempt
- Permit or allow any phase and overlap
individually for each preempt state
- Presence preempt input with optional fail-safe
interlock input
- “Check-in / Check-out” preempt detection option
with check-out override timer
- 4 soft preempts
- “Step-by-step” preempt (special preempt
sequence)
- 8 states per soft preempt sequence (timed or
actuated)
- Each state allows programmable calls, omits,
holds, and force-offs for each phase and overlap
Transit Priority Features
- Programmable transit priority options for each
transit phase
- Operates based on estimated arrival times using
local intersection detection and remote (“peer-to-peer”) detection from
upstream intersections
- Separate options for free or coordinated
operation
- Extend only (no phase abbreviation) or Early/Extend
operation
- Minimum phase green times
- Maximum extend limit
- Optional vehicle/pedestrian phase omits
- Ability to switch to alternate sequence to
better serve early arriving transit vehicle
- Adaptive arrival times to automatically compensate
for fluctuating station dwell times
Status / Diagnostic
Features
- Detailed controller status displays through the
2070 LCD display
- Phase, ring, and overlap status
- Transit phase/priority status
- Coordination status
- Preemption status
- Vehicle and pedestrian detector status
- Cabinet / Field I/O status
- System communication status
- 6000 controller event log
- Multiple classes of events can be individually
enabled for logging
- Retrieved and reset from central connection
(serial or Ethernet)
- 62.5 day detector VOS log
- Log VOS for 16 system detectors each 15 minutes
- 600 MMU event log
- Detailed MMU events, including reason for
failure and state of field outputs
Cabinet Support
- NEMA TS1, TS2-Type 1 and Type 2, Caltrans 332/336, and ITS cabinet support
- All controller input and output functions can be
mapped to any physical cabinet input and output
- “Peer-to-Peer” interconnect over Ethernet
(select outputs or inputs from the source intersection to activate a
function at the local intersection)
- Cabinet logic channels to accomplish custom
controller I/O operation
Protocol Support
- Communications over serial port, twisted pair,
or Ethernet (fiber-optics)
- Caltrans AB3418E with extended messages for extended
status and D4 specific functionality
- Future NTCIP compliance