Addressable control units MDD-S2

MDD-S2 addressable alarm output units are used to control optical and acoustic alarm devices in the Digital Gas Detection System (DGDS). It is possible to control alarm devices with a nominal voltage of 12VDC e.g. SL-32, SL-21, S-3x, LD-2.

MDD-S2 can be mounted anywhere on the RS-485 bus (outside the explosion hazard zone) and have two 12VDC alarm outputs.


  • two 12VDC alarm outputs with the possibility of connecting optical and acoustic alarm devices;
  • RS-485 port, MODBUS RTU protocol, galvanically isolated;
  • “non-contact” testing (magnetically, without opening the case);
  • 24VDC power supply from the bus with a single FTP cable;
  • can be added anywhere on the bus;
  • RS-485 bus terminator can be set;
  • all terminals are screwless, removable;
  • signalling terminals with the possibility of connecting multistrand wires (no crimping of sleeves) guarantees a very simple and quick connection/installation and easy maintenance;
  • mechanically resistant housing;
  • configuration of the module settings via the MDD-256/T supervisor module (manually using the front panel keyboard) or via the dedicated “MDD256 View” configuration software, available at

Offered models

Model Maximum number of detectors Power supply backup Supply voltage Net price C/G
MDD-S2 RS-485 24VDC PLN259.00 N