Single Reader Expansion Module (ADC-ACX1) - Data Sheet
Alarm.com’s Smarter Access Control is an ideal solution for any small or medium-sized business. The Single Reader Expansion Module is designed to add one extra reader to an Alarm.com door controller. Each ADC-ACX1 adds one reader port, two relay outputs, and two programmable inputs to the system. Connect the expansion module to the controller using a shielded, RS-485 twisted pair.
Note: It is always recommended to power the ADC-ACX1 with 12 VDC, as the input voltage is passed through to power the attached reader.
For larger commercial installations, Single and Two Reader Expansion Modules can be daisy-chained together.

Module features
- Provides all I/O needed for a single door using one reader
- One reader input
- Two relay outputs
- Two programmable inputs
- For use with Alarm.com Door Controllers
Smarter Access Control benefits
- Scan-to-add card format and serial detection
- Control doors and manage users from the Alarm.com Alarm.com app
- Integrated Alarm.com intrusion and video offerings
- User-friendly, flexible scheduling
- Configure hardware using web or app for easy installation
- Plug & play installation — no networking expertise required
Specifications
| Input Power |
12/24V DC, 150mA max, 110mA nominal @ 12V 60mA nominal @ 24V |
|---|---|
| Output Power | Input voltage pass-through |
| Communication | 2-Wire RS-485 |
| Inputs |
One dedicated reader input Two programmable inputs One dedicated tamper input |
| Outputs |
Two relay outputs (2A @ 30V DC) Single-wire LED control Single-wire buzzer output |
| Certifications |
UL 294 recognized CE compliant ROHS |
| Dimensions | 2.75 x 4.25 x 1.0” (70 x 108 x 25.4 mm) |
| Temperature |
-40 – 167°F (-40 – 75°C) operational -67 – 185°F (-55 – 85°C) storage |
| Operating Humidity | 0-95% (non-condensing) RH |

Developed with the Authentic Mercury open hardware platform