An  insulating powder is  enclosed in a cavity of two concentric spheres. The inner

space of the inner sphere contains the mica heater controled by the dimmerstat. The

tappings on the surfaces of the inner sphere and outer sphere are used to find out the

temperature difference between the spheres.

SPECIFICATIONS:

1.  Inner sphere dia. 100mm and outer sphere dia. 200mm.

2.  Ten thermocouple tappings in the test section.

3.  Plaster of Paris / asbestos powder in the test section.

4.  Voltmeter and ammeter,Dimmerstat,Temperature indicator