Fire Alarm Loop Controller Dynamic Voltage Adjustment

Solution Overview

Problem

Existing fire alarm systems face issues with significant voltage drops and electric shock hazards due to high drive voltage requirements, leading to device failures and safety concerns, especially in long loops with multiple devices.

Innovation Solution

A controller dynamically adjusts the alarm drive voltage based on loop resistance and expected voltage drops, ramping up voltage and current over time to maintain system functionality while reducing shock hazards during maintenance and normal operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If high drive voltage is continuously supplied to accommodate loop resistance and voltage drop, then sufficient power is provided to devices, but device failures and electric shock hazards increase

Engineering Contradiction:

Improvepower deliveryVSAvoiddevice lifespan

Core Design Contradiction:

PowerVSReliability

Solution Approach 1:

The system dynamically adjusts the drive voltage based on operational conditions. During alarm conditions, the voltage is increased to accommodate the significant voltage drop across the loop. During normal operation, the voltage is reduced to safe levels. This dynamic adjustment resolves the contradiction by providing high power only when necessary while maintaining safety and reliability during normal operation.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes the voltage parameter based on the operational state. The controller monitors alarm conditions and adjusts the drive voltage parameter accordingly - increasing it during alarms to ensure sufficient power delivery, and reducing it during normal operation to prevent device failures and electric shock hazards.

Inventive Principle:

Principle #35Parameter changes

2Power

If high drive voltage is continuously supplied to accommodate loop resistance and voltage drop, then sufficient power is provided to devices, but electric shock hazards increase

Engineering Contradiction:

Improvepower deliveryVSAvoidelectric shock hazard

Core Design Contradiction:

PowerVSObject-affected harmful factors

Solution Approach 1:

The system dynamically adjusts the drive voltage based on operational conditions. During alarm conditions, the voltage is increased to accommodate the significant voltage drop across the loop. During normal operation, the voltage is reduced to safe levels. This dynamic adjustment resolves the contradiction by providing high power only when necessary while maintaining safety during normal operation.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system applies high voltage periodically only during alarm conditions rather than continuously. The controller monitors the system state and applies high drive voltage only when an alarm is detected, otherwise maintaining safe voltage levels. This periodic application of high voltage eliminates continuous electric shock hazards while ensuring power availability when needed.

Inventive Principle:

Principle #19Periodic action

3Power

If high drive voltage is continuously supplied to accommodate significant voltage drop during alarm, then alarm devices receive sufficient power, but device lifespan is shortened

Engineering Contradiction:

Improvealarm power deliveryVSAvoiddevice lifespan

Core Design Contradiction:

PowerVSDuration of action of stationary object

Solution Approach 1:

The system dynamically adjusts the drive voltage based on operational conditions. During alarm conditions, the voltage is increased to accommodate the significant voltage drop across the loop. During normal operation, the voltage is reduced to safe levels. This dynamic adjustment resolves the contradiction by providing high power only when necessary while maintaining safety and reliability during normal operation.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes the voltage parameter based on the operational state. The controller monitors alarm conditions and adjusts the drive voltage parameter accordingly - increasing it during alarms to ensure sufficient power delivery, and reducing it during normal operation to prevent device failures and extend device lifespan.

Inventive Principle:

Principle #35Parameter changes

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 solution prevents device failures and electric shock hazards by optimizing voltage and current delivery, ensuring the fire alarm system's effectiveness and safety without continuous high drive voltage, while allowing for reduced power draw during maintenance.

Implementation Method 1

determine a resistance associated with an addressable fire alarm loop

Methodology Applied

Scientific EffectElectrical Resistance: Electrical Resistance

Implementation Method 2

determine an expected voltage drop in the loop during an alarm condition based on a plurality of devices of the loop

Methodology Applied

Scientific EffectElectrical Resistance: Electrical Resistance

Data Source

PatentUS10832557B2Operating a fire alarm system

Publication Date: 2020.11.10 HONEYWELL INTERNATIONAL INC

AI summary

Devices, systems, and methods for operating a fire alarm system are described herein. One device includes circuitry to determine a resistance associated with an addressable fire alarm loop during a quiescent condition, determine an expected voltage drop in the loop during an alarm condition based on a plurality of devices of the loop, and set an alarm drive voltage of a power supply associated with the loop based on the resistance and the expected voltage drop.