MESSKO® MTraB® 2.5

Maintenance-free dehydrating breather

Your benefits
at a glance

  • Massive cost savings, because the costly regular replacement of the desiccant is no longer necessary
  • Minimized risk of transformer failure, thanks to active humidity control
  • Design and function in accordance with the new IEC 60076-22-7 standard
  • Easy integration into the ETOS® Embedded Transformer Operating System
  • Simple retrofitting or replacement for existing equipment

Proven technology and worldwide practical experience –
The success story of the dehydrating breather

The maintenance-free dehydrating breathers of the MESSKO® MTRAB® product family minimize the ingress of moisture into the insulating fluid of transformers, tap changers and other electrical equipment filled with insulating fluids. We have improved the proven quality even further for the new 2.5 generation.

Conventional dehydrating breathers are filled with desiccants that have to be replaced depending on how saturated the medium becomes. The silica gel in the MESSKO® MTRAB® products, located in the silica gel chamber, is dehydrated by a built-in heating element that is controlled by sensors. This minimizes the need for periodic visual inspections and eliminates the high costs incurred through having to regularly replace the costly desiccant because it has become saturated.

In normal operation, the air flowing to the oil conservator is directed across the desiccant (silica gel), which dries it in the process. The degree of humidity of the air in the pipeline is measured constantly by a humidity sensor, and the results are transmitted to the electronic control unit. If the moisture content (humidity, % rH) of the air in the pipeline exceeds the value of 20% specified in the IEC 60076-22-7 standard, the self-regulating heating element in the silica gel chamber will activate, depending on the control mode (listed below). The water vapor escaping from the silica gel condenses on the specially shaped bottom section and drips out of the unit.

The temperature sensor enables the control system to monitor the correct operation of the heating element. An additional heating system (optional) can also be used to prevent the filter system from freezing in low outside temperatures. The temperature value measured in the pipeline (dehydrating breather) is issued as an analog signal by the control system. Faults in the control system / heating system are signaled via a failsafe live contact.

The current portfolio of maintenance-free dehydrating breathers consists of the MTRAB® 2.5 product family.

These are available in 3 sizes and 3 main versions:

  • α-control: Condition-dependent control of the heating process via humidity monitoring.
  • β-control: Self-learning system with condition-dependent control of the heating process via humidity monitoring, and temperature-dependent determination of the most favorable heating time.
  • γ-control: System for applications with an irregular breathing pattern. Thanks to the humidity monitoring function, the dehumidification chambers can be regenerated in alternation, depending on the condition.

More than 15 years of experience gained with customers has been channeled into the latest developments and improvements for the MESSKO® MTRAB® 2.5:

  • Data logger included as standard (optional software required)
  • Optional: Modbus RTU via RS485
  • Additional second analog output for humidity values and breathing pattern
  • Improved LED visibility, thanks to new arrangement
  • Failsafe relay as changeover contact
  • Service-friendly product design
  • Development in accordance with IEC 60076-22-7 (new standard for transformer accessories – self-regenerating dehydrating breathers)
  • Extended overvoltage protection in accordance with EN 60664-1 Category III
  • IP66/IP67
  • Test button for performing a self-test as standard

The test button is supplied as standard with the new generation of maintenance-free dehydrating breathers. The following functions are therefore available to all users:

  • Information on the current status of the device (including humidity level) can be queried at any time
  • Acknowledgement of error messages
  • Initiation of a self-inspection with advanced functions (function, signal paths and heating test)


How do you optimize the health index of your equipment?

The ever-increasing operating times of power transformers, coupled with a constantly increasing load, lead to ever-increasing demands on the equipment. Optimal dehumidification is essential to the reliability and long-term operating readiness of your system: the MESSKO® MTRAB® is your perfect partner for this task.

  • Safeguard the function of the transformer system.
  • Lengthen the service life of the transformer system.
  • Protect the investment and the asset with regard to the transformer system.

The primary objective is the long-term cost assurance of your entire business model.

Benefits of the maintenance-free dehydrating breather

In contrast to conventional dehydrating breathers, which have to be regularly inspected, cleaned, and replaced, you save on both inspection and maintenance costs when using the MESSKO® MTRAB®. Moreover, a maintenance-free system prevents possible leaks due to service errors whereby non-desiccated ambient air can interact directly with the insulation medium.

Equipped with optimized temperature and humidity sensors in combination with intelligent and proven algorithms for automatic regeneration of the silica gel, the MESSKO® dehydrating breather reduces the risks and uncertainties that arise with a conventional dehydrating breather that is not maintained or replaced regularly.

The MESSKO® solution – More than 15 years of experience in the field

Our successful track record thus far: Tens of thousands of MTRAB® units in use around the world, and millions upon millions of hours of maintenance-free operation in 24/7 mode. With the new generation of MESSKO® MTRAB® 2.5, we are continuing this trend with state-of-the-art technology.

  • 6,500 MESSKO® MTRAB® customers in 180 countries

  • Installation sites with very different conditions –
    whether in a rainforest, in a desert, in the arctic region or for offshore applications.