If you are planning an access control system using Suprema's CS-20 (or CS-20P) and DI-24 expansion modules, it is crucial to understand how many readers and doors the system can ultimately support. This article explains the architecture and provides clear calculations to help you plan your project effectively.



System Overview

CS-20/CS-20P (CoreStation 20)

  • Relevant Article: [BioStar 2] New Product Introduction - CoreStation 20
  • Supports 4 direct reader connections via RS-485 at either RS-485 port 0 or 1.
  • It allows the connection of up to 16 DI-24 expansion modules via RS-485 at the RS-485 port on the top of the device.

DI-24 (Door Interface)

Door Setup Rule

  • 2 readers are required for 1 door (e.g., one for entry, one for exit)



Maximum System Capacity

Let us calculate the maximum number of readers and doors supported by a single CS-20 unit with full expansion.

1. Readers directly connected to CS-20
→ 4 readers

2. Readers from 16 DI-24 modules
→ 16 modules × 4 readers = 64 readers

3. Total Readers
→ 4 (CS-20) + 64 (DI-24) = 68 readers

4. Total Doors
→ Since 2 readers are needed per door:
68 ÷ 2 = 34 doors



Summary

With 1 CS-20 and 16 DI-24 modules:

  • Total Reader Capacity: 68 readers
  • Total Door Capacity: 34 doors

This configuration is ideal for facilities requiring multi-point access control and expandability.