Addressable control units MDD-N1

MDD-N1 interface units are used to connect a single dual-threshold detector to the Digital Gas Detection System (DGDS). MDD-N1 processes alarm signals of a dual-threshold detector and the relay output fault, and sends them to the supervisory module (MDD-256/T). The MDD-N1 with the connected detector occupies one address in the detectors’ address space (it is treated as a „detector” by the DGDS supervision module).


  • 3 voltage-free inputs (controlled from the external system’s relayoutputs), including 2 configurable to connect external 12VDC alarm outputs;
  • 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;
  • all screwless terminals, removable;
  • input terminals with the possibility of connecting multi-strand wires (no crimping of sleeves) = very simple and quick connection/installation, easy maintenance;
  • tight, mechanically resistant housing;
  • configuration of the module settings via the MDD-256/T supervisory module (manually using the front panel keyboard) or via the dedicated „DETnet View” configuration software, available at

Offered models

Model Maximum number of detectors Power supply backup Supply voltage Net price C.g.
MDD-N1 RS-485 24VDC PLN259.00 N
Model Maximum number of detectors Alarm control outputs 12VDC Contact control outputs Emergency control output Output controlling the shut-off valve Alarm inputs Analogue 4-20mA output Analogue 2-10V output Digital RS-485 output Mounting on a TS35 rail Power supply backup Supply voltage Dimensions Net price C.g.
MDD-N1 RS-485 3 24VDC 92 x 82 x 55 mm PLN259.00 N