Containing a large nonvolatile memory that can hold up to 406,323 states, the State101A is a data logger that is commonly used to record the on-off status of machinery and electronics. It has a 4-Hz reading rate and a 10-year battery life. Features include optional password protection, a battery-life indicator, and a manual start-stop function that can be executed multiple times without the need to download data between studies. The State101A is built for use in applications such as examining the efficiency of heating and cooling systems; monitoring power supply on-off statuses; and evaluating gas, water, and electrical pumps. With programmable engineering units available, users have the ability to convert data into a variety of units, such as on-off and opened-closed. Using the manufacturer’s software, starting, stopping, and downloading from the State101A is simple and easy. Data can be displayed in graphical, tabular, and summary views and may also be automatically exported to Microsoft Excel® for additional analysis.