A controller quotation is only as accurate as the intersection information behind it. “Eight-phase traffic controller” may describe the required movement plan, but it does not tell the supplier how many signal groups, pedestrian outputs, detector inputs, timing plans or communication ports the cabinet needs.
Use this checklist when requesting a controller for a permanent intersection, private road, work zone or solar installation. It helps the engineer size the outputs and cabinet around the actual operating plan instead of guessing from a product name.
Start with one marked intersection drawing
Provide a plan view showing every approach, lane arrow, pedestrian crossing and stop line. Give each controlled movement a simple label, then use the same labels in the phase sequence and bill of quantities. For a temporary shuttle system, show the length of the one-lane section and the position of both signal units.
The first technical review should answer four questions: which movements may run together, which movements conflict, how long users need to clear the controlled area, and what the system should do after a fault.
Controller RFQ data sheet
| Section | Information to send | Why it is needed |
|---|---|---|
| Intersection | Number of approaches, lane use, crossings and site drawing | Establishes the movement structure |
| Phases | Movement sequence and permitted simultaneous movements | Defines logic and conflict monitoring |
| Signal groups | Vehicle balls, arrows, pedestrians, bicycles and countdowns | Determines output count and terminal plan |
| Electrical | Site supply, signal-head voltage and backup requirement | Sizes power distribution and protection |
| Detection | Loops, radar, video, push buttons or other inputs | Defines input cards and operating modes |
| Communication | Local port, Ethernet, cellular, fiber or central-system protocol | Determines interfaces and integration work |
| Cabinet | Indoor/outdoor, mounting, climate, spare capacity and cable entry | Defines enclosure and internal layout |
| Documents | Drawings, manuals, test records, language and tender forms | Sets the approval and handover scope |
Separate phases from signal groups
A phase represents a traffic movement or timing function; a signal group is the set of outputs that displays its indications. The counts are related but not interchangeable. One vehicle phase may operate several red-yellow-green heads, and the intersection may also need separate arrow, pedestrian, bicycle or countdown outputs.
List every signal group and the number of heads connected to it. Include the electrical details of the heads so output load and monitoring can be reviewed. Browse the 3-aspect signal range or the complete LED traffic light catalog when preparing the head schedule.
Describe fixed-time, actuated and manual operation
For fixed-time control, provide the required plans, cycle lengths, splits and schedule changes. For actuated control, mark each detector or push button and describe the movement it calls or extends. If the controller must support police control, a gate contact, remote handset or maintenance flash, explain the priority of those inputs and the desired return to normal operation.
Do not assume that “adaptive” has the same meaning to every supplier. Name the central system or protocol, provide the interface specification, and define which data points must be exchanged.
Permanent cabinet, portable base or solar enclosure
A permanent roadside controller usually needs power distribution, surge protection, output switching, terminal blocks, maintenance controls and space for communications or detector equipment. A portable controller base adds transport, battery, manual controls, weather protection and quick-connect cabling. An off-grid solar controller also needs an energy budget and autonomy target based on the signal load and local solar conditions.
State whether the request is for a controller board, a populated cabinet or a complete operating system. The same controller name can otherwise produce offers with very different scope.
Documents and factory checks to include
- Approved intersection phase plan and conflict table.
- Cabinet general arrangement and terminal schedule.
- Power and signal wiring diagrams.
- Configuration instructions and backup method.
- Input/output test record for the supplied cabinet.
- Model-specific compliance documents requested by the tender.
- Spare parts list and recommended field test equipment.
Where central-system integration is required, agree on a bench test using the actual protocol and data-point list before shipment.
A concise controller inquiry example
Four-arm intersection with two vehicle phases, two protected-turn phases and four pedestrian crossings. Signal heads are project-specified AC units; supply is 220–240 VAC. Inputs include four pedestrian push buttons and four radar detectors. Outdoor base-mounted cabinet required, with one spare output group and Ethernet communication. Please quote the populated cabinet, programming tool, English drawings, terminal schedule, factory I/O test and recommended two-year spare parts.
This short description still needs a drawing and timing plan, but it gives the supplier enough structure to ask the right follow-up questions.
Controller RFQ FAQ
How many phases should I request?
Count the independently timed movements in the approved plan, then allow for pedestrian, bicycle and special movements. Have the controller engineer confirm phase and output capacity from the drawing.
Should spare capacity be included?
Reasonable spare inputs, outputs and cabinet space can simplify later changes, but excessive capacity adds cost and complexity. State any known future movement or detector plans.
What is needed to quote a portable traffic light controller base?
Provide the number of signal units, shuttle distance, sequence, battery or mains supply, cable or radio method, manual controls, expected runtime, enclosure arrangement and transport constraints.
Can the controller operate countdown timers?
Yes when the output or communication method matches the display. Identify the countdown model and intended mode early; see the countdown selection guide.
Review the traffic signal controller category, then send the intersection drawing and I/O list for a project-specific configuration.
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