Defining the term weatherproof for motor frames

[edison123]

I have received a very old GE (USA) DC machine for refurbishment. This motor has an blower unit mounted on the frame above the commutator. The blower sucks in the atmospheric air and the hot air exits from the vents in the opposite side.

The nameplate states this is weatherproof enclosure. When the blower takes in atmospheric air and the hot air exits from open vents, how is this considered weatherproof enclosure? Am I misunderstanding the term?

Muthu

http://www.edison.co.in

 

[ashtree]

I am sure someone will know this terminology better than me and I may be wrong on this but this sounds very much like the old British Standard definition where terms like drip proof and weatherproof were used.

I think weatherproof meant it could withstand rain at up to an angle of 45 degrees from vertical without damaging anything. How that fits with your machine I am not sure but many of those older machines tended to be of a quite open with ventilation in the lower half of the end housings but designed to protect against rain from above.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[jraef]

Here are the official MEMA definitions. They didn't use the term weather "proof" however.

Weather-Protected Machine:
Type 1 (WPI) weather-protected machine is an open machine with its ventilating passages so constructed as to minimize the entrance of rain, snow and airborne particles to the electric parts and having its ventilating openings so constructed as to prevent the passage of a cylindrical rod 3/4 inch in diameter.

Weather-Protected Machine:
Type II (WPII) shall have, in addition to the enclosure defined for a type 1 weather-protected machine, it’s ventilating passages at both intake and discharge so arranged that high velocity air and airborne particles blown into the machine by storms or high winds can be discharged without entering the internal ventilating passages leading directly to the electric parts of the machines shall be so arranged by baffling or separate housing as to provide at least three abrupt changes in direction, none of which shall be less than 90 degree. In addition, an area of low velocity not exceeding 600feet per minute shall be provided in the intake air path to minimize the possibility of moisture or dirt being carried into the electric parts of the machine.


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[edison123]

Thanks Guys. It's clear I have misunderstood.

Muthu

http://www.edison.co.in