Dickson chart recorders are mechanical devices that consist of a paper chart rotating around a central hub. While rotating, a pen on an articulating arm is drawing on the rotating chart. The pen arm moves based on the readings of either a sensor or bimetal (a specialised piece of metal that expands and contracts based on the temperature).
Each pack of charts consist of 60 pieces. The chart refills comes in 2 sizes:
- 4 inches (101mm)
- 6 inches (152mm)
The 4 inches (101mm) Chart provides a 24-hour recording, can take temperature measurements ranging from -30°C to 50°C.
The 6 inches (152mm) Chart provides 7-day recording with temperature measurements ranging from:
- 0°C/F to 100 °C/F or
-100°C/F to 0°C/F