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Scientific, testing, calibration and other precision equipment can be very expensive and often requires precise storage and handling to ensure correct operation.  For protecting equipment against damaging humidity, a cabinet fitted with a Rosahl micro-dehumidifier offers significant benefits over alternative air drying cabinets and desiccant solutions.

Unlike silica gel and other desiccants, Rosahl micro-dehumidifiers offer a new way to protect electro-optics and micro-electronics from moisture damage.  Membrane dehumidifiers use electrolysis to remove moisture from an enclosure: they operate continuously and without the need for regularly replacement or recharging in order to retain their moisture absorbing capacity.

Moisture sensitive devices MSDs

MSDs include electronic components encapsulated with plastic compounds and other organic materials. Moisture from the environment can enter permeable packaging materials and collects at the interfaces of dissimilar material. Moisture absorption and retention inside electronic packages cause problems such as trapped moisture that can vaporize and exert internal package stresses when the device is subjected to sudden, elevated temperature, such as during reflow soldering .

Cabinet for protecting equipment

Cabinets equipped with membrane micro-dehumidifiers are also suitable for storing moisture sensitive devices in production areas. Membrane dehumidifiers use a solid polymer electrolyte (SPE) that removes water vapour by electrolysis when a 3VDC charge is applied to the terminals.  SPEs are designed for use in small sealed enclosures from one litre to 4 cubic metres, depending on the model. They are economical to operate, have a long operating life, and have no moving parts to are noiseless and vibration free.


One of the advantages of electrolysis is that the dehumidification process does not involve liquid water, making the process maintenance free. No drainage system means no emptying, no cleaning, no pipes and no mould, improving both reliability and cost of ownership the cost.

Low energy dehumidifier

Low energy consumption is another important consideration.  The compact size of membrane dehumidifiers ensures that they have low power consumption and the annual average power consumption of the largest membrane is about 10 Watts.

Membrane micro-dehumidifiers are best used in cabinets and enclosures that are sealed against further moisture ingress, and typical applications include:

  • Precision equipment storage cabinets
  • Museum displays and exhibition cabinets
  • Storage of hygroscopic materials
  • Semiconductor manufacturing
  • FTIR spectrometers
  • LED and laser systems
Precise humidity control for cabinets
Advantages of Rosahl dehumidifiers