Glossary

Term	Description
Rated voltage	The maximum voltage at which electric component can operate for extended periods without undue degradation or safety hazard.
Reader	A device that obtains data from an access credentials (card, tag, etc.) and send the data to a controller for an access decision. (Some units combine reader and keypad in one device.)
Relay	An electrically controlled device that opens and closes electrical contacts to effect the operation of other devices in the same or another electrical circuit.
Resistor	A circuit element whose chief purpose opposes the flow of current, causing a decrease in voltage.
REX	A REX (request to exit) is used to determine if someone is waiting at the door. It can be ultrasonic, infra-red or simply a button. It is usually installed on the inside of the door and is used to automatically unlock the door if someone wants to leave a building. In most cases, a badge is not required to leave a building (although in some circumstances this may not be true). A REX sensor would then let the panel know that someone wants to leave, and react by the panel unlocking the door for them if programmed so.
Routing Level	A Routing Level is Computer based or workstation based. A Routing Level determines whether or not Events or Alarms are sent to specific computers. Different events may not be important to an operator across the building or campus from the operator. A Routing Level provides the computer to filter out the events that are important to it.
RTU	A generic term that represents any equipment or software with which Intelli-Site integrates. A card reader, a DVR, a RFID reader, are all examples of RTUs.
RTUs	More than one RTU, a generic term that represents any equipment or software with which Intelli-Site integrates. A card reader, a DVR, an RFID reader, are all examples of RTUs.