MDD-R4/T Digital RS-485 output TS35

Device group: Addressable control units
Device type: MDD-R4/T

MDD-R4/T digital executive units are designed to expand the Digital Gas Detection System (DGDS). They enable local control of actuators/signalling devices for a selected group of up to 32 detectors working in the DGDS. They have four relay outputs and two 12VDC alarm outputs.

MDD-R4/T are units that require MDD-256/T type supervisory unit in the system. Communication with the supervisory unit is carried out in the industrial standard RS-485, compliant with the MODBUS RTU protocol. The MDD-R4/T control unit cyclically receives information from the supervisory unit about the alarm status of a selected group of detectors and realizes the set alarm functions by switching on the optical alarm signaling and activating its own relay and 12VDC alarm outputs.


  • simple setup of independent groups/detectors zones (max. 32 pieces per group) with local control of actuators (max. 3 MDD-R4/T units per group):
  • communication with MDD-256/T type supervisory module in RS-485 standard (MODBUS RTU, galvanically isolated port);
  • optical indication of relay output states OUT1, OUT2, OUT3, OUT4;
  • alarm outputs 12VDC OUT5 and OUT6, to control acoustic and optical signaling devices;
  • contact outputs (galvanically separated) OUT1, OUT2, OUT3 and OUT4, to control fans, motors, contactors, information boards or to connect with building/plant automation;
  • all removable terminals, with the possibility of connecting wires and cables (without sleeves), allow the use of cost-effective installation materials; quick installation, commissioning and replacement;
  • enclosure for TS35 rail mounting in standard electrical switchgear;
  • configuration of unit settings via the MDD-256/T supervisor unit (manually using the front panel keyboard) or via the dedicated configuration software „MDD256 View”, available at

Device model: MDD-R4/T

Technical parameters

Alarm control outputs 12VDC
Contact control outputs
Emergency control output
Digital RS-485 output
Mounting on a TS35 rail
Supply voltage
106 x 90 x 65 mm
EAN Code
Net price
PLN469.00 N


Series Technical data Device information sheet Instruction manual Declaration of conformity
W3 Download file

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