Standard Motor Catalog

Section TR Technical Reference Guide

V. REFERENCE NEMA VERSUS IEC MOTORS: A BRIEF OVERVIEW

Rodent Screens - Rodent screens will be provided where required as part of the dripproof guarded system and with specific request of the purchaser. SHAFT SEALS (LIP SEAL/NON-CONTACT LABYRINTH SEAL)

1.0 Standards Organizations Standard

NEMA (National Electrical Manufacturers Association)

Function

A North American based trade association comprised of 450+ member companies that manufacture electrical transmission and distribution, control, and other electrical type equipment. IEC (International Electrotechnical Commission) A global organization that prepares and publishes international standards for all electrical, electronic and other related technologies.

Web Address www.nema.org Standard

Figure 34

Function

Non-contact Labyrinth seals are metallic seals with rubber sealing rings, which provide protection against both dust and liquids. Lip seal (contact type) consists of a spring loaded rubber circular lip. The spring loaded lip prevents entry of dust and liquid particles inside the motor.

Web Address www.iec.ch

2.0 Motor Output

Table 42: NEMA Output Ratings - Expressed in HP (Horsepower) IEC Output Ratings - Expressed in kW (Kilowatts) IEC (kW) Rating NEMA (HP) Rating IEC (kW) Rating NEMA (HP) Rating 0.37 0.5 55 75 0.55 0.75 75 100 0.75 1 90 125 1.1 1.5 110 150 1.5 2 132 - 2.2 3 150 200 3.7 5 160 - 4 5.4 185 250 5.5 7.5 200 - 7.5 10 220 300 11 15 250 350 15 20 280 - 18.5 25 300 400 22 30 315 - 30 40 335 450 37 50 355 - 45 60 375 500 Note: kW ratings shown in bold text are not typical for standard IEC motors. (Shown only for reference to NEMA comparable HP ratings)

Either of the above seals are provided on request.

The following tabulation (Table 41) lists the sealing arrangement where shafts emerge from the motor bearing housings.

Table 41: Shaft Seals

Motor Frame

143 449

509

5013

TECHNICAL REFERENCE GUIDE

GE Motor Enclosure

Shaft Seal

Standard Dripproof Totally Enclosed Severe-duty Enclosed

F F S S

F F S S

XSD Ultra ®

Explosion-proof

F*

F*

IEEE-841 API-661

L L

L

Not Applicable

F = Close running fit at both ends. S = Neoprene slinger steel reinforced DE and ODE. L = Non-contact Labyrinth seals. * Except Class II Group E motors which have non-sparking labyrinth seals.

TR.48

Data subject to change without notice. 03/24 • www.wolongamerica.com