School of Physics Lecture Demonstration Manual

Eg-3 The Pilot Lamp

Published: Tuesday 14 March 2006 - Updated: Tuesday 29 March 2011


To demonstrate how the pilot lamp uses a thermoelectric magnet as a safety feature.



Click on pictures to enlarge.

Pilot Lamp Pic


The pilot lamp consists of a thermoelectric magnet connected to a valve. While the pilot lamp is on the heat generated activates the themoelectric magnet and this in turn allows gas to flow to the Pilot lamp circuit. If the Pilot lamp extinguishes the magnetic field collapses and closes the valve cutting off the supply of gas to this part of the circuit. The lever arm has been attached to the electromagnet so that movement of the valve can be clearly seen.

Safety notes

Electrical safety 

Fire/Burn safety 


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