The Didactum Dry Contact Expansion Unit adds up to 32 potential‑free/digital input contacts to your high‑end monitoring systems for IP‑based remote supervision. Optionally, this number can be increased to 64 inputs using an additional board—ideal for large infrastructures with extensive fault reporting and building technology.

Fully CAN‑bus compatible, the unit integrates seamlessly into existing Didactum installations. This enables trouble reporting systems, heating, ventilation, and air conditioning (HVAC), backup power systems, and fire alarm technology to be incorporated into central network monitoring without difficulty.

IP and TCP/IP connectivity for switch and alarm contacts

Using the integrated RJ12 CAN port, the Dry Contact Unit connects directly to the Didactum monitoring system. All connected inputs are automatically recognized via the web interface (Autosense), allowing immediate configuration.

Up to 8 units per CAN port are supported, with a maximum cable length of 225 meters per run. This allows deployment in large buildings or distributed technical centers.

Flexible configuration and alerting

Through the browser‑based web front‑end, each input can be assigned a unique name and its default state (NO—normally open / NC—normally closed). Individual alarm actions can be defined for each contact:

• SNMP traps to central network management systems
• Immediate email notifications
• SMS alerts via optional GSM modem
• Relay output for direct control of building systems

All events are logged in the monitoring system’s syslog and can be retrieved at any time.

Typical applications

• Building technology: Central monitoring of doors, windows, alarm systems, or HVAC units.
• HVAC systems: Integration of heating, ventilation, and air‑conditioning controls into IT monitoring.
• Backup power: Monitoring status messages from UPS and diesel generator systems.
• Fire alarm systems: Remote fire alarm reporting via IP‑based alerting systems.

Easy installation

The Dry Contact Unit is supplied with a 2‑meter RJ12 patch cable. A 2‑wire signal cable is used for wiring to the switch contacts. Thanks to the modular CAN structure, the expansion can be quickly integrated into existing systems.

Scalability and Daisy‑Chain support

Daisy‑Chain support allows the creation of large monitoring networks. Adding an optional extra Dry Contact Board increases the input capacity to a total of 64 ports.

Extended contact monitoring for professional infrastructure

The Didactum Dry Contact Expansion Unit offers maximum flexibility for monitoring up to 64 potential‑free contacts via IP. Easy to install, fully configurable, and equipped with integrated alert functions, it ensures the highest operational reliability—perfect for industrial applications, building management, and critical infrastructure.