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Nema Electrical Motor Frame Dimensions

Reference data and engineering information about nema electrical motor frame dimensions for electrical applications.

nemaelectricalmotorframe

Overview

NEMA (National Electrical Manufacturers Association) standardizes motor frame dimensions to ensure interchangeability between manufacturers. The 1984 NEMA standard defines key mechanical dimensions for mounting and shaft interfaces. Frame numbers (42, 48, 56, 140T, etc.) encode approximate shaft height and frame size. Suffixes like C (C-face mounting), H (larger mounting hole spacing), and J/P (jet pump shaft) indicate mounting or shaft variants.

NEMA Frame Dimensions — Small Frames (42–56)

Dimensions in inches. Blank cells indicate the dimension is not specified for that frame.

10 rows
NEMA motor frame dimensions for frames 42 through 56 (1984 standard)
NEMA Frame
D (in)
E (in)
2F (in)
BA (in)
N–W (in)
U (in)
422.6251.751.68752.06251.1250.375
42C2.6251.751.68752.06251.1250.375
4832.1252.752.51.50.5
48C32.1252.752.51.50.5
48H32.1254.752.51.50.5
563.52.437532.751.8750.625
56C3.52.4375—2.751.8750.625
56H3.52.437552.751.8750.625
56HZ3.52.437552.752.250.875
56J3.52.4375—2.752.43750.625

Source: engineeringtoolbox.com

NEMA Frame Dimensions — Larger Frames (66–143)

6 rows
NEMA motor frame dimensions for frames 66 through 143 (1984 standard)
NEMA Frame
D (in)
E (in)
2F (in)
BA (in)
N–W (in)
V (in)
U (in)
664.1252.937553.1252.25—0.75
140T3.52.7542.752.25—0.875
142AT3.52.753.252.751.751.50.875
143AT3.52.7542.251.751.50.875
143JM3.52.7542.25——0.875
143JP3.52.7542.25——0.875

Source: engineeringtoolbox.com

Dimension Reference

KeyDescription
DShaft center height (distance from base to shaft centerline)
EDistance from shaft shoulder to mounting bolt center
2FMounting bolt hole center-to-center distance (lengthwise)
BAMounting bolt hole center-to-center distance (widthwise)
N–WShaft extension length from face
VThread length on shaft
UShaft diameter

Restored Original Source Tables

The following tables are restored from the original source page to preserve the complete reference data.

2 rows
Original source layout/search table preserved for completeness; it is not NEMA frame-dimension engineering data.
Source cell 1
Source cell 2
Source cell 3
Source cell 4
Source cell 5
××検索
×

Source: engineeringtoolbox.com

Electrical Motors - NEMA Frame Dimensions

168 rows
Electrical Motors - NEMA Frame Dimensions
NEMA Frame Designation
Frame Dimensions (inches)
Frame Dimensions (inches)
Frame Dimensions (inches)
Frame Dimensions (inches)
Frame Dimensions (inches)
Frame Dimensions (inches)
Frame Dimensions (inches)
DE2FBAN-WVU
422 5/81 3/41 11/162 1/161 1/83/8
42C2 5/81 3/41 11/162 1/161 1/83/8
4832 1/82 3/42 1/21 1/21/2
48C32 1/82 3/42 1/21 1/21/2
48H32 1/84 3/42 1/21 1/21/2
563 1/22 7/1632 3/41 7/85/8
56C3 1/22 7/162 3/41 7/85/8
56H3 1/22 7/1652 3/41 7/85/8
56HZ3 1/22 7/1652 3/42 1/427/8
56J3 1/22 7/162 3/42 7/165/8
664 1/82 15/1653 1/82 1/43/4
140T3 1/22 3/442 3/42 1/47/8
142AT3 1/22 3/43 1/42 3/41 3/41 1/27/8
143AT3 1/22 3/442 1/41 3/41 1/27/8
143JM3 1/22 3/442 1/47/8
143JP3 1/22 3/442 1/47/8
143T3 1/22 3/442 1/42 1/427/8
143TC3 1/22 3/442 3/42 1/47/8
143TR3 1/22 3/442 1/42 5/81 3/47/8
144AT3 1/22 3/44 1/22 3/41 3/41 1/27/8
145AT3 1/22 3/452 3/41 3/41 1/27/8
145JM3 1/22 3/452 1/47/8
145JP3 1/22 3/452 1/47/8
145T3 1/22 3/452 1/42 1/427/8
145TC3 1/22 3/452 3/42 1/47/8
145TR3 1/22 3/452 1/42 5/81 3/47/8
146AT3 1/22 3/45 1/22 3/41 3/41 1/27/8
146ATC3 1/22 3/45 1/22 3/42 1/47/8
147AT3 1/22 3/46 1/42 3/41 3/41 1/27/8
148AT3 1/22 3/472 3/41 3/41 1/27/8
149AT3 1/22 3/482 3/41 3/41 1/27/8
1410AT3 1/22 3/492 3/41 3/41 1/27/8
1411AT3 1/22 3/4102 3/41 3/41 1/27/8
1412AT3 1/22 3/4112 3/41 3/41 1/27/8
1412ATC3 1/22 3/4112 3/42 1/47/8
162AT43 1/842 1/21 3/41 1/27/8
163AT43 1/84 1/22 1/21 3/41 1/27/8
164AT43 1/82 1/22 1/21 3/41 1/27/8
165AT43 1/85 1/22 1/22 1/21 3/41 1/27/8
166AT43 1/86 1/42 1/21 3/41 1/27/8
167AT43 1/872 1/21 3/41 1/27/8
168AT43 1/882 1/21 3/41 1/27/8
169AT43 1/892 1/21 3/41 1/27/8
1610AT43 1/8102 1/21 3/41 1/27/8
1824 1/23 3/44 1/22 3/42 1/427/8
L182ACY4 1/23 3/44 1/22 3/42 1/427/8
182AT4 1/23 3/44 1/22 3/42 1/421 1/8
L182AT4 1/23 3/44 1/22 3/421 1/8
182JM4 1/23 3/44 1/22 3/47/8
182JP4 1/23 3/44 1/22 3/42 3/47/8
182T4 1/23 3/44 1/22 3/42 3/42 1/21 1/8
182TC4 1/23 3/44 1/22 3/42 3/41 1/8
182TR4 1/23 3/44 1/22 3/42 1/42 1/41 1/8
183AT4 1/23 3/452 3/42 1/421 1/8
1844 1/23 3/45 1/22 3/42 1/427/8
184AT4 1/23 3/45 1/22 3/42 1/421 1/8
184JM4 1/23 3/45 1/22 3/47/8
184JP4 1/23 3/45 1/22 3/47/8
184TC4 1/23 3/45 1/22 3/42 3/41 1/8
184T4 1/23 3/45 1/22 3/42 3/42 1/21 1/8
184TR4 1/23 3/45 1/22 3/43 3/82 1/41 1/8
185AT4 1/23 3/46 1/42 3/42 1/421 1/8
186ACY4 1/23 3/472 3/42 1/427/8
186AT4 1/23 3/472 3/42 1/421 1/8
L186AT4 1/23 3/472 3/42 1/421 1/8
186ATC4 1/23 3/472 3/42 1/41 1/8
187AT4 1/23 3/482 3/42 1/421 1/8
188AT4 1/23 3/492 3/42 1/421 1/8
189AT4 1/23 3/4102 3/42 1/421 1/8
189ATC4 1/23 3/4102 3/42 1/41 1/8
1810AT4 1/23 3/4112 3/42 1/421 1/8
203545 1/23 1/82 1/423/4
204546 1/43 1/82 1/423/4
2135 1/44 1/45 1/23 1/232 3/41 1/8
213AT5 1/44 1/45 1/23 1/22 3/42 1/21 3/8
213JM5 1/44 1/45 1/23 1/27/8
213JP5 1/44 1/45 1/23 1/21 1/4
213T5 1/44 1/45 1/23 1/23 3/83 1/81 3/8
213TC5 1/44 1/45 1/23 1/23 3/81 3/8
213TR5 1/44 1/45 1/23 1/24 1/82 5/81 3/8
214AT5 1/44 1/46 1/43 1/22 3/42 1/21 3/8
2155 1/44 1/473 1/232 3/41 1/8
215AT5 1/44 1/473 1/22 3/42 1/21 3/8
215JM5 1/44 1/473 1/27/8
215JP5 1/44 1/473 1/21 1/4
215T5 1/44 1/473 1/23 3/83 1/81 3/8
215TC5 1/44 1/473 1/23 3/81 3/8
215TR5 1/44 1/473 1/24 1/82 5/81 3/8
216AT5 1/44 1/483 1/22 3/42 1/21 3/8
217AT5 1/44 1/493 1/22 3/42 1/21 3/8
218AT5 1/44 1/4103 1/22 3/42 1/21 3/8
219AT5 1/44 1/4113 1/22 3/42 1/21 3/8
219ATC5 1/44 1/4113 1/22 3/41 3/8
2110AT5 1/44 1/412 1/23 1/22 3/42 1/21 3/8
2110ATC5 1/44 1/412 1/23 1/22 3/41 3/8
2245 1/24 1/26 3/43 1/232 3/41
2255 1/24 1/27 1/23 1/232 3/41
253AT6 1/4574 1/43 1/431 5/8
2546 1/458 1/44 1/43 3/83 1/81 1/8
254AT6 1/458 1/44 1/43 1/431 5/8
254T6 1/458 1/44 1/443 3/41 5/8
254TC6 1/458 1/44 1/441 5/8
254TR6 1/458 1/44 1/44 1/22 7/81 5/8
254U6 1/458 1/44 1/43 3/43 1/21 5/8
255AT6 1/4594 1/43 1/431 5/8
256AT6 1/45104 1/43 1/431 5/8
256T6 1/45104 1/443 3/41 5/8
256TC6 1/45104 1/441 5/8
256TR6 1/45104 1/44 1/22 7/81 5/8
256U6 1/45104 1/43 3/43 1/21 3/8
257AT6 1/45114 1/43 1/431 5/8
258AT6 1/4512 1/24 1/43 1/431 5/8
259AT6 1/45144 1/43 1/431 5/8
283AT75 1/284 3/43 1/43 1/21 7/8
28475 1/29 1/24 3/43 3/43 1/21 1/4
284AT75 1/29 1/24 3/43 3/43 1/21 7/8
284T75 1/29 1/24 3/44 5/84 3/81 7/8
284TC75 1/29 1/24 3/44 5/81 7/8
284TR75 1/29 1/24 3/44 3/43 1/81 7/8
284TC75 1/29 1/24 3/43 1/431 5/8
284U75 1/29 1/24 3/44 7/84 5/81 5/8
285AT75 1/2104 3/43 3/43 1/21 7/8
286AT75 1/2114 3/43 3/43 1/21 7/8
286T75 1/2114 3/44 5/84 3/81 7/8
286TC75 1/2114 3/44 5/81 7/8
286TR75 1/2114 3/44 3/43 1/81 7/8
286TS75 1/2114 3/43 1/431 7/8
286U75 1/2114 3/44 7/84 5/81 7/8
287AT75 1/212 1/24 3/43 3/43 1/21 7/8
288AT75 1/2144 3/43 3/43 1/21 7/8
289AT75 1/2164 3/43 3/43 1/21 7/8
323AT86 1/494 3/44 1/442 1/8
32486 1/410 1/25 1/44 7/84 5/81 5/8
324AT86 1/410 1/25 1/44 1/442 1/8
324TR86 1/410 1/25 1/45 1/43 1/22 1/8
324TS86 1/410 1/25 1/43 3/43 1/21 7/8
324U86 1/410 1/25 1/45 5/85 3/81 7/8
325AT86 1/4115 1/44 1/442 1/8
32686 1/4125 1/44 7/84 5/81 5/8
326AT86 1/4125 1/44 1/442 1/8
326T86 1/4125 1/45 1/452 1/8
326TR86 1/4125 1/45 1/43 1/22 1/8
326TS86 1/4125 1/43 3/43 1/21 7/8
326U86 1/4125 1/45 5/85 3/81 7/8
327AT86 1/4145 1/44 1/442 1/8
328AT86 1/4165 1/44 1/442 1/8
329AT86 1/4185 1/44 1/442 1/8
363AT97105 7/84 3/44 1/22 3/8
3649711 1/45 7/85 5/85 3/81 7/8
364AT9711 1/45 7/84 3/44 1/22 3/8
364S9711 1/45 7/83 1/431 5/8
364T9711 1/45 7/85 7/85 7/82 3/8
364TR9711 1/45 7/85 3/43 3/42 3/8
364TS9711 1/45 7/83 3/43 1/21 7/8
364U9711 1/45 7/86 3/86 1/82 1/8
3659712 1/45 7/85 5/85 3/81 7/8
365AT9712 1/45 7/84 3/44 1/22 3/8
365T9712 1/45 7/85 7/84 7/82 3/8
324T86 1/410 1/25 1/45 1/452 1/8
365TR9712 1/45 7/85 3/43 3/42 3/8
365TS9712 1/45 7/83 3/43 1/21 7/8
365U9712 1/45 7/86 3/86 1/82 1/8
366AT97145 7/84 3/44 1/22 3/8
364AT9711 1/45 7/84 3/44 1/22 3/8
367AT97165 7/84 3/44 1/22 3/8
368AT97185 7/84 3/44 1/22 3/8
369AT97205 7/84 3/44 1/22 3/8

Source: engineeringtoolbox.com

Original Source Images

The following original source images are preserved to avoid losing visual reference material. When an image contains chart or tabular data, its extracted values are represented in the page tables, calculators, or interactive charts; remaining images are retained as visual source references.

NEMA motor frame - dimensions

Interactive NEMA Frame Dimension Diagram

NEMA Motor Frame Dimension Keys

Engineering Notes

Motor Frame Dimension Converter

  • C-face suffix: Frames ending in C (e.g., 48C, 56C) indicate a C-face (close-coupled) mounting pattern. The 2F dimension is typically not specified because C-face motors mount by their face rather than a base.
  • H suffix: Motors with the H designation have a wider 2F mounting pattern than their base frame, accommodating larger mounting bases.
  • T suffix (140T, 143T): Indicates a "T-frame" designation introduced in 1964 to replace older frame sizes. T-frames are the current standard.
  • J and P suffixes (56J, 143JM, 143JP): Denote jet pump motor shafts with threaded shaft ends for direct impeller attachment.
  • HZ suffix (56HZ): Specifies a frame with both wider mounting holes and a modified shaft dimension.
  • These dimensions are per the NEMA MG-1 1984 standard. Modern motors may follow updated revisions; always verify against the applicable specification revision.

References

Source: engineeringtoolbox.com