Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


Defining the term weatherproof for motor frames

Defining the term weatherproof for motor frames

Defining the term weatherproof for motor frames

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?


RE: Defining the term weatherproof for motor frames

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.

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

RE: Defining the term weatherproof for motor frames

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.

"You measure the size of the accomplishment by the obstacles you had to overcome to reach your goals" -- Booker T. Washington

RE: Defining the term weatherproof for motor frames

Thanks Guys. It's clear I have misunderstood.


Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close