Keri Systems NXT-4X4 Input/Output Expansion Module

Expand and simplify door-level monitoring and control with the Keri Systems NXT-4X4 input/output expansion module. Designed for Doors.NET access control systems, this control panel module delivers localized security I/O — ideal for door forced/held open alarms, auxiliary REX inputs, bond sensors and other monitoring tasks — while minimizing cable bundles back to the controller. Each module provides 4 auxiliary inputs and 4 auxiliary outputs and connects anywhere along the RS-485 trunk for flexible placement near readers or doors. When paired with NXT controllers you can scale capacity (one module per trunk; up to additional I/O on NXT-2D and NXT-4D systems) to meet growing access control and surveillance needs. Re-assignable relays mirror controller functions for easy integration into existing action sequences, and flash memory ensures simple firmware updates. Built with security installations in mind, the unit includes LED status indicators and an optional locking metal enclosure for tamper-resistant mounting. Add the NXT-4X4 to your security or access control project to streamline wiring, expand monitoring, and strengthen door-level surveillance — contact our sales team to configure and order.

• Localize door control and alarms to the door, reducing cable runs and simplifying installation
• Adds 4 auxiliary inputs and 4 auxiliary outputs per module; scales to additional I/O (up to 16 inputs/outputs with compatible NXT controllers)
• Connects anywhere on the RS-485 trunk for flexible placement and easy network integration
• Re-assignable relays fully interchangeable with controller door I/O for versatile access control logic
• Flash memory upgrades, LED status indicators and optional locking metal enclosure for secure, maintainable installations