Motor Frame Size Lookup

Free NEMA motor frame size lookup. Decode frame designations into mounting dimensions in your browser — no upload, no login. For distributor catalog enrichment.

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Paste a motor frame designation like 145T, 56, or 215TC and this tool decodes the NEMA motor frame size into its standardized mounting dimensions — shaft height, bolt-hole pattern, shaft diameter, and keyseat — so you can enrich a catalog record or confirm two parts are mechanically interchangeable. It is built for distributors and MRO teams who receive frame numbers in supplier feeds but need the underlying dimensions to populate product attributes.

Motor Frame Size Lookup

The interactive version of this tool is coming soon. It will run entirely in your browser — no login, no upload limits.

Planned tool: nema motor frame size

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What it checks

  • Frame validity — confirms the designation matches a recognized NEMA frame number (for example 42, 48, 56, 143T, 145T, 182, 184T, 213T, 215T, 254T, 256T, and larger integral-horsepower frames).
  • Dimension decoding — returns the standardized D (shaft height from base to centerline), 2E and 2F (bolt-hole spacing), BA, shaft diameter U, and keyseat for the entered frame.
  • Suffix interpretation — explains mounting and construction suffixes such as T (current standard dimensions), U (older standard), C (C-face flange), D (D-flange), H, J, M, N, S (short shaft), and Z.
  • Interchange check — flags whether two frames share the same mounting footprint, so you can tell a true drop-in replacement from a near match that needs a base adapter.
  • Footprint summary — produces a clean, copy-ready set of attribute values you can drop into a PIM, ERP, or marketplace listing.

How NEMA motor frame size is structured

A NEMA frame number is not arbitrary. For most foot-mounted motors, the first two digits encode the shaft height: divide them by 4 to get the distance in inches from the bottom of the feet to the shaft centerline. A 145T frame has a 3.5-inch shaft height (14 ÷ 4); a 215T frame sits at 5.25 inches. The remaining digit or digits fix the distance between mounting-bolt holes, and the letter suffix records the dimensional series and any flange. Because these values are published in the NEMA MG 1 standard, any two motors with the same frame and suffix share the same bolt pattern and shaft — which is exactly what makes the frame number such a powerful enrichment key.

This tool runs entirely in your browser. Nothing you paste is uploaded to a server, stored, or logged — the frame lookup table and the dimension math execute client-side, so even confidential supplier price lists or pre-launch SKUs stay on your machine. That matches how the same logic should run inside an automated pipeline: deterministic decoding from a known standard, never a guess.

FAQ

How do I read a NEMA motor frame number?

Take the first two digits and divide by 4 to get the shaft-center height in inches above the mounting feet. A 56 frame is 3.5 inches; a 213T frame is 5.25 inches. The next digit sets the bolt-hole spacing, and the letter suffix records the dimensional series and any flange. The tool above does this decoding for you and returns the full dimension set.

What does the 'T' in a frame like 145T mean?

The T indicates the current NEMA standard dimensions, adopted in the mid-1960s. Older motors used a U series (for example 145U) with slightly different shaft diameters and lengths. A T and a U of the same number are not direct interchanges, which is why the suffix matters when you are matching a replacement part.

Are two motors with the same frame size interchangeable?

Mechanically, a shared frame and suffix means the same bolt pattern, shaft height, shaft diameter, and keyseat — so they bolt up identically. Electrical interchangeability is separate: voltage, horsepower, speed, efficiency, and enclosure still have to match. Use this tool for the mechanical footprint, then confirm the electrical attributes in your record.

What is the difference between a C-face and a foot-mounted frame?

A foot-mounted frame (no flange letter) bolts down through its feet. A C suffix adds a C-face flange with a male register and tapped bolt holes for coupling directly to a pump or gearbox. The base frame number still drives the shaft dimensions; the suffix tells you how it mounts.

Can I enrich a whole catalog of motors this way?

For one-off lookups this tool is enough. For thousands of SKUs, the same deterministic decoding should run inside a pipeline that reads the frame field, expands it into structured attributes, and records where each value came from. That is the approach covered in the provenance guide linked above and built into Claro’s enrichment layer.