Experimental evaluation of the surface thermal response of connection systems in low-voltage single-phase circuits
DOI:
https://doi.org/10.37135/ns.01.18.10Keywords:
Low voltage, Localized heating, Electrical connectors, Thermal rise, Electrical splice, Infrared thermographyAbstract
This study experimentally evaluated the surface thermal response of connection systems used in low-voltage single-phase circuits with progressive loads. Two-way lever connectors and a twisted branch splice were analyzed in a 127 V circuit using 12 AWG copper conductors. The surface temperatures of the connection point and the adjacent conductor were recorded using infrared thermography for 120 min under each condition. The analysis considered the temporal evolution of temperature, the thermal rise relative to the initial state, and the surface propagation of heat toward the conductor. The results showed differentiated thermal responses even under equivalent electrical conditions. The 221-682 and 221-412 connectors exhibited the lowest thermal rises and more limited heat propagation toward the conductor. The P04-2P showed an intermediate response, whereas the twisted branch splice reached an intermediate-high condition. In contrast, the generic connector exhibited the most critical behavior, reaching a final temperature of 85.1 °C under the highest load. It is concluded that initial electrical continuity does not guarantee equivalent thermal performance among connection methods; therefore, the evaluation should consider maximum temperature, temporal evolution, thermal rise, and heat propagation toward the conductor.
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References
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