Control module MDD-ZW 2 control outputs for MAG-3 valves, 2 inputs for valve closing confirmation, standard enclosure IP54

Shut-off valve control module – reliable protection for gas installations

This addressable control module MDD-ZW, manufactured by GAZEX, is designed to work with MAG-3 shut-off valves in Digital Gas Detection Systems (DGDS). It enables remote valve control, significantly increasing the safety and efficiency of the entire system. The module is not limited to DGDS – it can work with various GAZEX MD alarm modules, as well as with external systems equipped with a 12V= alarm output.

Functionality and application

MDD-ZW is a versatile device used in smart buildings, public facilities, gas-heated halls, and logistics and warehouse bases. It allows controlling from 1 to 4 MAG-3 valves (in two independent zones), offering configuration flexibility. Thanks to the RS-485 communication port (MODBUS RTU protocol), the module integrates with building automation and monitoring systems.

The module also allows connecting a manual shut-off switch, which provides additional security and allows manual control over valve closure. This is particularly important in emergency situations or during installation maintenance. Importantly, MDD-ZW is a replacement for MD-X.ZA24/2 and MD-X.ZA/2 models, which simplifies the modernization of existing systems.

Safety and diagnostics

A key element of the module's functionality is monitoring the valve status. Two inputs for confirming valve closure with limit switches ensure that the valve is properly closed after a hazard is detected. The built-in FAULT contact output signals any problems with the module, lack of valve connection, lack of closure confirmation (for valves with closure control), faulty internal battery, or incorrect supply voltage. Optical and acoustic signaling informs about the alarm status, and the ability to mute the acoustic signal ensures user comfort. Additionally, the module allows manual valve testing directly on the device.

Universal 12/24V= power supply ensures compatibility with various electrical installations. The housing with IP54 protection degree protects against dust and moisture, guaranteeing reliable operation even in harsh environmental conditions. The length of the communication bus between MDD-ZW and the extreme element of the DGDS system can be up to 200 meters, providing a great deal of freedom in device placement.