A thermometer formed wholly of dielectric components inserted between the coils of a transformer winding immersed in cooling fluid within the case of a high voltage transformer, the thermometer having a rod responsive to temperature changes within the case to vary light transmission across terminals...http://www.google.es/patents/US3960017?utm_source=gb-gplus-sharePatente US3960017 - Thermometer insertable in winding of fluid cooled transformer
Thermometer insertable in winding of fluid cooled transformer
