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The 'quarter-power equation' for resistive heating faults
1MJC-FFE Ltd, The Heath Business and Technical Park, Runcorn Cheshire, England WA7 4QX, United Kingdom.
Science & Justice : Journal of the Forensic Science Society
|March 12, 2022
Summary
Electrical fire investigations can now utilize the
Area of Science:
- Electrical Engineering
- Fire Science
- Forensic Investigation
Background:
- Electrical faults are a common cause of fires.
- Resistive heating faults are a principal type of electrical fire ignition.
- Existing power transfer calculations are not widely applied in fire investigations.
Purpose of the Study:
- To adapt electrical power transfer principles for fire investigation.
- To introduce the 'quarter-power equation' for analyzing resistive heating faults.
- To provide guidance on the application and limitations of this new equation.
Main Methods:
- Re-working the power transfer relationship by defining the circuit as the supply and the fault as the load.
- Deriving the 'quarter-power equation' based on this modified circuit analysis.
- Analyzing the equation's utility and limitations in a practical fire investigation scenario.
Main Results:
- The 'quarter-power equation' provides a method to assess the viability of resistive heating faults as an ignition source.
- The equation was successfully used to eliminate a potential fire cause in a specific investigation.
- Guidance on the equation's derivation, application, and limitations is presented.
Conclusions:
- The 'quarter-power equation' is a valuable tool for fire investigators analyzing electrical fires.
- This method enhances the scientific rigor of determining fire origins.
- The study demonstrates a novel application of electrical engineering principles in forensic science.
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