Model AT4 is an extremely versatile 24 Hour 365 Day Event Timer designed to support a wide range of applications. Such applications include: Home and Building Automation, Security, Access Control, Lighting Control, Etc. AT4 is equipped with four independently controlled form C relay contacts that provide many latching and/or momentary operations during a program schedule of your choice. The EE prom memory allows for programming of unit prior to/or during field installation. Events may be set for single or multiple operations on a daily and/or weekly schedule. The block programming feature enables repeating an event on any combination of consecutive days. AT4 will compensate for daylight savings time if desired. It automatically adjusts for leap year and is Y2K compatible. Individually selected holiday exceptions can be programmed to over-ride regularly scheduled events.