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. • 12 to 24 volts AC or DC operation • Standby current: 20mA with relays off combined with 40mA for each relay on. • Four (4) Form “C” relay contacts are rated 10amp @120VAC/28VDC. • EE Prom memory protects against loss of programming due to power failure. • Clock synchronization 60Hz (AC operation). • Accurate crystal controlled clock (DC operation). • Momentary and/or Latching Events. • 254 individually programmed daily/weekly events. • Block programming capacity can accommodate a total of 1778 events per week. • 254 programmable Holiday events. • “First man in” option. • Alphanumeric LCD display simplifies programming. • Standard or Daylight Savings Time settings. • Automatic compensation for leap year. • Each relay operates independently. • Built-in charger for 12VDC sealed lead acid or gel type batteries (Max charge current 300mA). • Lithium battery backup maintains clock. • User friendly keyboard programming. • Unit is Y2K compatible. Enclosure dimensions: 12.25”H x 7.75”W x 4.5”D