MD-1, MD-2, MD-4

MD-1, MD-2 and MD-4 dual-threshold alarm modules are designed to control and supply 1/2/4 of the DEX/F, DEX/A, DG/F or DG.EN type threshold gas detectors for use in the Dual Threshold Gas Detection System and Active Gas Safety System GX (ASBIG®).

The alarm module can control from one (MD-1) to two (MD-2) or up to four (MD-4) detectors. The module can control additional external optical and acoustic signaling devices and enables communication with other devices via relay outputs (or an RS-485 port for MD-1…).

Modules in MD…Z version can control a gas shut-off valve. Such module is a component of “the signalling and shut-off system” according to the requirements of the Regulation of the Minister of Infrastructure of the Republic of Poland dated April 12, 2002 on technical conditions to be met by buildings and their location (Journal of Laws 2002 No. 75 + changes).


  • power supply for dual-threshold detectors (with load control and wired connection);
  • optical indication and memory of the detector’s alarm states and control outputs;
  • Alarm input (for A2, galvanically separated) for fire systems or manual valve switch;
  • 12VDC alarm outputs – supply of additional acoustic and optical signalling devices;
  • relay outputs (galvanically separated) - control of fans, contactors, information boards;
  • relay output “FAULT” (galvanically separated) - informs about emergency state of the module or power failure;
  • power supply of additional module for remote control of valves;
  • for MD…Z: high-current output 12VDC to control a MAG-3 type shut-off valve (with connection control);
  • automatic power supply backup (for MD-1.Z version);
  • in /M version: RS-485 port for connection to the Digital Gas Detection System or for configuration/reading of event memory data to PCs via dedicated configuration software “DETnet View”, available at

Block diagram

Offered models

Name Maximum number of detectors Power supply backup Supply voltage Net price C/G
MD-1 New product 1 230VAC 299.00 zł S
MD-1/M New product RS485 1 230VAC 399.00 zł N
MD-2 2 230VAC 349.00 zł S
MD-4 4 230VAC 449.00 zł S
MD-2.A 2 12VDC 349.00 zł S
MD-4.A 4 12VDC 449.00 zł S
MD-1.A24 New product 1 24VDC 299.00 zł S
MD-1.A24/M New product RS485 1 24VDC 399.00 zł N
MD-2.A24 2 24VDC 359.00 zł N
MD-4.A24 4 24VDC 459.00 zł N
With shut-off valve control output
MD-1.Z New product 1 230VAC 399.00 zł S
MD-1.Z/M New product RS485 1 230VAC 499.00 zł N
MD-2.Z 2 230VAC 509.00 zł S
MD-4.Z 4 230VAC 539.00 zł S
MD-2.ZA 2 12VDC 509.00 zł S
MD-4.ZA 4 12VDC 539.00 zł S
MD-1.ZA24 New product 1 24VDC 399.00 zł S
MD-1.ZA24/M New product RS485 1 24VDC 499.00 zł N
MD-2.ZA24 2 24VDC 539.00 zł N
MD-4.ZA24 4 24VDC 569.00 zł N

Suggested products

Service batteries AKU-07GX
Batteries designed to generate a control pulse for the shut-off valve in MD-...Z type control units
GSM modems
Devices designed for remote monitoring of gas detection system status
Installation switch SW-20
Double switch for 230 AC power supply