The CONTACTlogger™, Model TOU-C, for monitoring relay closures, switches, and digital on/off signals. TOU SMARTloggers are single channel, on-off status data loggers. They are designed to provide Total On-Time and Time-Of-Use (TOU) information about energy consuming devices with a constant power draw as well as the operating schedule for any device. The TOUs record the time to the second that a device turns on, and then again when it turns off. The data saved to the logger’s memory is a series of on-off transitions and time stamps.