The module can be connected anywhere along the RS-485 trunk, most commonly at the controller or near a reader. One module can be added per trunk, allowing up to an extra 8 inputs and 8 outputs on an NXT-2D Controller and an extra 16 inputs and outputs on an NXT-4D controller.

• Flash Memory for easy upgrades
• Re-assignable/Interchangeable with controller's door I/O
• 4 auxiliary Inputs and 4 auxiliary Outputs per module
• One 4x4 module can be added to each controller bus
• 4-State Supervision on Inputs
• Powered from Controller or by stand alone power supply
• Status Indicator LEDs for power, communication, and relay position
• Optional Locking Metal Enclosure