SDC 423UL1G /Security Door Controls 423UL1G Access Controller - Image 2
SDC 423UL1G /Security Door Controls 423UL1G Access Controller - Image 2
SDC 423UL1G /Security Door Controls 423UL1G Access Controller - Image 3
SDC 423UL1G /Security Door Controls 423UL1G Access Controller - Image 4
SDC 423UL1G /Security Door Controls 423UL1G Access Controller - Image 5
SDC 423UL1G - Image 5
SDC/Security Door Controls 423UL1G Access Controller
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Description

Discontinued — No Longer Available New

This model has been discontinued by SDC. Shop current SDC products → or see the recommended alternatives below.

SDC/Security Door Controls 423UL1G Access Controller

Overview

The SDC 423UL1G is a networked access control controller engineered for mid to large-scale installations requiring multi-door management and credential flexibility. It delivers centralized control across up to 63 doors with support for 250,000 user records, making it suitable for enterprise facilities, multi-tenant buildings, and integrated security deployments.

Key Specifications

Door Capacity: 63 doors | User Capacity: 250,000 users | Voltage: 24VDC | Credential Support: DESFire, MIFARE, NFC/13.56MHz, 125kHz Proximity | Communication: OSDP and TCP/IP protocols | Function: DPDT relay, 1-60 second adjustable timing (green indicator)

Compatibility

Integrates with OSDP-compliant readers and access control systems supporting TCP/IP network deployment. Compatible with DESFire and MIFARE smart cards, NFC badges, and legacy 125kHz proximity credentials, allowing mixed-credential environments without reader replacement. Designed for installers requiring protocol flexibility and scalable multi-door architectures.

Expert Analysis
Specifications
Product Type: Controller
Communication: OSDP, TCP/IP
Door Capacity: 63 doors
Voltage: 24VDC
Type: Controller
Input Voltage: 24VDC
Doors Supported: 63 doors
Credential Type: DESFire, MIFARE, NFC/13.56MHz, 125kHz Proximity
Max Users: 250,000
Reader Type: Multi-credential reader support
eol: true
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SDC/Security Door Controls 423UL1G Access Controller

$124.99
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