Circular chart recorders archive data points on a round chart over a timed interval. Using data acquired by one or more sensors, circular chart recorders rotate uniformly while one or more pens plots the data radially in proportion to the signal received. The charts usually rotate over standard time periods (e.g. 24 hours, one week, one month, etc.) though some recorders can rotate over non-standard lengths of time. The benefits of circular chart recorders includes the ease of operation, the hardcopy it produces, and real-time output.

Common applications for circular chart recorders include temperature and humidity measurements, flow rates, pH, pressure, as well as a host of other process measurements. Circular chart recorders are available in single or multichannel styles and in various configurations. Many recorders can also record information in a digital format for download to a computer. Circular chart recorders require the correct charts and pens to work correctly. 

Membrane switches are particularly suitable for such applications and portable devices because they are lightweight, low profile, durable and easy to clean.