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Some discussions can be made over the type of bearing used. Comair has performed numerous tests and has found that the ball bearing system works exceptionally well. It is not recommended to use sleeve bearings in an environmentally protected fan. The ball bearings are double shielded which resists most contaminants from entering the bearing surfaces.
As a brief outline as to what type of protection is best suited for your needs, consider the following:
- Type 1 protection is intended for environments that included exposure to water mists, sprays, dripping, dust, condensation, and moderate vibrations.
- Type 2 protection is intended for harsher environments that include exposure to ocean salts in the form of fog or a mist. Type 2 protection also provides extra protection to the fan for excessive shock and vibration.
- Type3 protection is also intended for harsh salt fog environments but included additional protection to the motor windings. Type 3 protection also provides extra protection to the fan for excessive shock and vibration.
Type 1 Environmental Protection
Type 1 environmental protection is a thin silicone coating that is applied to the complete motor assembly, including the motor windings, lamination stack, and the populated circuit board. The silicone material has a lower viscosity than most other materials; which allows the material to seep into and around all of the components and motor windings. The process for applying this material is typically by spraying 2 coats of the material to the motor assembly from several directions. This ensures good, uniform coverage of the material. Each motor assembly is thoroughly cleaned in a solvent bath to remove an oils or impurities before any protective material is applied. Cure time is within minutes, making this process quicker than the other more elaborate process. The material is also non-corrosive, fungus inert, and has a viable temperature range exceeding the range of fans.
Type 1 environmental protection is designed to meet mildly harsh environmental conditions. These conditions include the occasional spray of water to the fan (wash-down requirements), exposure to fine dust particles, morning dew that may condensate inside the fan, and other similar conditions. Type 1 protection will enhance the fans ability to resist moderate vibrations by acting as an adhesive to keep fragile electrical components such as resistors, diodes, and other small components. In general, this option is designed to meet standard specifications such as:
- Nema 12, 12K
- IP 54, 55, 56
Details of these specifications and their relevant requirements are available upon request.
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