Open Drip Proof (ODP) / Totally Enclosed Fan Cooled (TEFC)

[W@ttson]

Hello,

NEMA MG 1 and a lot of motor manufacturers list dimensions for various parts of the motors and minimum speeds etc depending on two categories, either Open Drip Proof or Totally Enclosed Fan-Cooled.

However, where does "Totally Enclosed Non-ventilated" motors fall into? Do they fall in ODP or TEFC?

The overall length for example of a motor will be greatly different if you slap a fan on the back of it rather than no fan. However, a TENV does not need a fan and shouldn't have that extended length.

 

[retirede]

Unlike critical mounting dimensions, the overall length (“C dimension) can vary from one manufacturer to the next. When designing equipment, we would get drawings from our possible suppliers, and use the largest dimension in the design.

That said, I’d expect a TENV “C” dimension to be closer to the ODP than TEFC.

 

[Jraef]

In a TENV motor, all of the rotor heat must dissipate through the shaft, so dimensions are often affected by what that entails. I would not make any assumptions. The idea of getting the dimensions from the supplier is the only way I would recommend dealing with this. They still will use standard NEMA frames in terms of mounting dimensions, but which BEMA frame they use for a given HP size may be different than fir a TEFC or ODP w equivalent.