Protection circuit assembly and method

Abstract

Single channel digital addressable lighting interface (DALI) systems can include a dedicated external power supply that operates in a constant voltage / constant current mode to meet requirements of the DALI bus. A lighting controller is powered from the DALI bus. In one embodiment of the inventive subject matter, a lighting system is provided that includes two or more control (e.g., DALI) buses and a multichannel power supply that can be used for powering a controller of the system with constant voltage and to power separate control buses with separate and constant current. In order to protect the controller and buses from overloads caused by miswiring or other erroneous conditions, a protection circuit assembly is provided.

Description

FIELD[0001]Embodiments of the inventive subject matter described herein relate to electric circuits that protect devices from damage or destruction.DISCUSSION OF ART[0002]Some electrical systems include controllers that control operations of other devices. Some of these systems can be lighting systems having a controller that communicates with light sources for controlling which light sources are activated or deactivated. The systems may include separate pathways or wires for supplying current to the light sources for powering the light sources and communicating with the light sources.[0003]One example of such as system is a digital addressable lighting interface (DALI) lighting system. The light sources are wired to a controller with two wires. One wire is a control bus for communicating control signals from the controller to the light source for controlling operation of the light sources and for communicating feedback signals form the light source to the controller for informing t...

AI Technical Summary

Benefits of technology

This patent describes a lighting system that has multiple protection circuits to control the operation of light sources. The protection circuits are connected to a power supply and separate control buses, which communicate control signals from a microcontroller to the light source drivers. The system also includes a transceiving circuit to communicate control signals to different groups of light sources via separate control buses. The protection circuits prevent an increase in voltage on one control bus from affecting other control buses. Additionally, the system has a temperature-sensitive protection circuit that prevents voltage from injecting into the control circuit when the circuit reaches a certain temperature.

Problems solved by technology

This can cause the light source to be miswired to the controller, such as when the mains voltage line and the control bus are incorrectly connected to the controller to connections intended for the other of the control bus or the mains voltage line.

As a result, the controller may receive too much voltage via the control bus and be damaged or destroyed by the voltage.

This can significantly increase the cost of implementing or establishing a DALI lighting system.

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