The DS1 delay/sequencer board offers a switching network that is ideal for (de)energizing an electrified locking device then, after an adjustable time, activating an automatic door operator. It is also suitable for other timing functions such as door sequencing in one or both directions, or anywhere a timing relay is required. For Telephone Entry system applications, the DS1 offers a direct connection to the entry panel, simplifying wiring and eliminating the need for and isolating relay.