Lighting Control Protocol Dynamic Poll ID Assignment

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing load control systems face challenges in communication due to the complexity of setting device addresses, leading to communication errors, and require a robust protocol that supports a free-wiring scheme while allowing timely execution of special events.

Innovation Solution

A novel communication protocol where a master device polls control devices with unique Poll IDs, allowing devices to request and assign IDs dynamically, and suspends normal polling for high-priority events, using a four-wire RS-485 communication link with differential signals for efficient data transmission.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If polling technique is used for communication between control devices, then reliable communication is achieved, but system response time for special events deteriorates

Engineering Contradiction:
Improvecommunication reliabilityVSAvoidresponse time for special events
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent implements dynamic polling intervals where the master device adjusts the timing of poll messages based on system conditions. Normal polling operates at standard intervals for reliable status monitoring, but the system can suspend or accelerate polling when high-priority events are detected, allowing adaptive response timing while maintaining communication reliability.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent ensures continuous communication monitoring by maintaining the polling mechanism as an ongoing process. Rather than interrupting communication entirely for special events, the system continues polling operations while prioritizing event handling, ensuring that reliable communication is maintained without complete interruption of the control loop.

Inventive Principle:
Principle #20Continuity of useful action

2Reliability

If DIP switches are used for device address assignment, then unique addressing is achieved, but device complexity and installation difficulty increase

Engineering Contradiction:
Improveunique device addressingVSAvoidaddressing mechanism complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical DIP switch system with an electronic soft-addressing mechanism. The master device electronically assigns unique Poll IDs to slave devices through communication protocols, eliminating the need for physical switch configurations. This substitution reduces mechanical complexity while maintaining reliable unique addressing through software-based device identification.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Ease of operation

If soft addressing procedure is used to assign device addresses, then ease of installation is improved, but communication errors may occur due to incorrect address assignment

Engineering Contradiction:
Improveease of device address assignmentVSAvoidcommunication reliability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The patent implements feedback mechanisms where slave devices confirm receipt and correct interpretation of their assigned Poll IDs by responding to master device queries. The master device verifies address assignment by receiving expected response messages from each slave, providing immediate feedback on successful addressing. This feedback loop prevents communication errors by ensuring addresses are correctly assigned and recognized before normal operation begins.

Inventive Principle:
Principle #23Feedback

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This protocol ensures reliable communication, reduces errors, and allows for timely handling of special events, enhancing the operational efficiency of load control systems by eliminating the need for DIP switches and enabling easy combination of separate lighting control systems.

Implementation Method 1

using a four-wire RS-485 communication link with differential signals for efficient data transmission

Methodology Applied
Scientific EffectDifferential signaling:

Data Source

PatentEP2119322B1Communication protocol for a lighting control system
Publication Date: 2023.06.07 LUTRON TECHNOLOGY COMPANY LLC
  • EP2119322B1 patent drawingFigure 1
  • EP2119322B1 patent drawingFigure 2
  • EP2119322B1 patent drawingFigure 3A~3B

AI summary

A communication protocol for a lighting control system having a plurality of control devices coupled to a communication link uses a polling technique to coordinate the transmission of digital messages between the control devices. When the control devices are powered up, one of the control devices is established as a "master" device. During normal operation, the master device transmits a standard poll message to each of the control devices in succession using a unique semi-permanent Poll ID for each of the control devices. The master device periodically transmits a Poll-ID-Request poll message to the control devices allow those devices that do not have a Poll ID to request a Poll ID. If a control device determines either that the master device is not transmitting poll messages to it, or that another control device has the same Poll ID, the control device drops its Poll ID and acquires another Poll ID.