Title: Hardware Installation Guide.pdf
8I1I11K, 1%1K, 1%NCDOOR CONTACT NORMALLY CLOSEDJ3TAMPER, NC328 — revision 6Hardware Installation GuideDoor contact and REx are selectable through the access control software (by default, door contact is normally closed and REX is normally open).62.1.2Upstream CommunicationThe Single Reader Interface Module uses Port 1 to communicate to the Intelligent System Controller.Port 1 is a 2-wire RS-485 interface, that requires the following type of RS-485 cable: 24 AWG (minimum) twisted pair (with shields). The main run RS-485 cable should be no longer than 4000 feet (1219 m), 100 ohms maximum (Belden 9841, West Penn, or equivalent). The drop cables (to downstream devices) should be kept as short as possible, no longer than 10 feet.The RS-485 communication is asynchronous, half-duplex, using 1 start bit, 8 data bits, 1 stop bit.