The Openpath 4-Port Expansion Board is an access control board (no enclosure, no power supply) that connects to the Access Control Core and supports up to four Openpath readers and four doors. The 4-Port Board works with the Access Control Core to securely make all entry decisions. It includes primary ports for Openpath readers and door hardware. For additional flexibility, two auxiliary relays are provided for additional outputs or control of low power devices and four auxiliary inputs are provided for Wiegand devices or additional sensors. The 4-Port Board uses RS-485 wiring to connect to the Smart Readers and connects by USB to the Access Control Core. The 4-Port Board should be installed inside an enclosure and may be powered using a 12V or 24V supply.