The 2100-810NG operates from a 120-volt 60-Hz power source. On the front of the calibrated heat source is a knob that lets you select one of five delta temperatures, ranging from 126°F to 220°F. The heat source contains a heat block that can reach a combined temperature of your delta temperature plus the ambient temperature. It can maintain this temperature for extended periods. The heat block temperature is controlled by a circuit that references both ambient temperature and the temperature of the heat block and maintains the selected differential. For example, if the ambient temperature were 29.4°C (85°F) and the knob were set to 180°F (100°C), the heat block would be maintained at 129.4°C (265°F).
Infrared scanners respond to rapid changes in infrared radiation. The calibrated heat source accomplishes the rapid changes by employing a rotating wheel with an aperture on one side. As the wheel turns, the infrared radiation from the heat block is shielded from the scanner until the aperture lines up with the opening in the bottom of the heat source case. The wheel rotates at 300 rpm.