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How to specify a Stepper Motor

What to put on an RFQ for Stepper Motor: the ratings, documents, and constraints that change the quote.

25 Oct 2026 · 3 min read · Tradinor Desk

Specification points for Stepper MotorTRADINOR · FIGUREWhat to lock for Stepper MotorPower and speedElectricalDutyEnclosure
Put these on the RFQ for Stepper Motor before you compare prices.

A buyer searching for Stepper Motor is usually trying to stop a bad substitute. A motor is specified by power, speed, voltage, duty, and the mechanical interface. The notes below are selection criteria for a Stepper Motor. They are not a catalog promise. Confirm every rating on the current datasheet, drawing, or test report for the revision you will receive.

What has to be true of Stepper Motor

A motor is specified by power, speed, voltage, duty, and the mechanical interface. For a Stepper Motor, start from the duty, then the interface to the rest of the machine or the room, then the document that proves the claim. A lower price that leaves one of those blank is a different product.

Stepper Motor is easy to confuse with Stepper Driver Motors. If the quote could be read as either, add the line that separates them: the rating, the fitment, or the standard named below. Link the drawing number to that line so receiving inspection can reject the wrong one.

Numbers that change the quote

Line What to write for Stepper Motor
Power and speed Kilowatts or horsepower and rpm at the rated point.
Electrical Voltage, phases, frequency, and current.
Duty Continuous or intermittent, and the ambient.
Enclosure The enclosure code and the mounting, such as foot or flange.
Interface Shaft size, and feedback if it is a servo.
Drive Whether it will run on a VFD. Insulation and bearing measures may change.

How to compare two offers

Lay both quotes for Stepper Motor on one sheet and line up power and speed, electrical, and duty. If a cell is empty, the offer is not finished. Ask for the missing line in writing. When those match, the honest difference is lead time, the test evidence, and who carries the warranty. Do not average a fully specified Stepper Motor with a cheaper line that omitted power and speed.

Documents worth having before the deposit

IEC 60034 is the usual rotating-machinery family. Ask which ratings on the nameplate follow it. The file should name Stepper Motor and the revision, not only the supplier’s homepage. A factory quality certificate such as ISO 9001 can sit beside that file. It does not replace it.

Failures that show up after delivery

  • Putting a standard motor on a VFD without asking about insulation and bearings.
  • Mismatching the shaft.
  • Forgetting the service factor or the duty.

On a Stepper Motor, the expensive version of the first mistake is discovering it after the goods are in the crate. Put the rejection condition in the purchase order while the supplier can still restate the offer.

A worked RFQ line

Use this shape, then replace the brackets with your duty: “Stepper Motor — State power, speed, voltage, phases, duty, and frame or shaft.” That sentence is a template, not a rating of any brand. If a supplier’s datasheet uses different units, convert them onto this sheet so the next offer can be compared.

Where words like waterproof / IP65 belong

Searches often add a constraint to Stepper Motor: waterproof / IP65, or automotive grade. Keep those on this page. IP65 in IEC 60529 means dust-tight and protected against water jets. Write that code if hoses are the real exposure. The word waterproof alone does not name a test. Automotive grade is a temperature, vibration, and documentation claim. Ask which AEC or customer spec is actually met, and for which part number. If you need a third constraint, add it as another line on the same drawing. A second URL that only swaps the adjective does not give a buyer a second fact.

Related in this section: how to specify Stepper Driver Motors.

Questions buyers actually ask

What should an RFQ for Stepper Motor include?

State power, speed, voltage, phases, duty, and frame or shaft.

Is a cheaper Stepper Motor the same part?

Only if power and speed, electrical, and the documents match. A missing line is a different offer.

Do waterproof, OEM, or IP words need their own page?

No. For Stepper Motor they are extra lines on this specification. Ask for the test or the drawing that gives the word a value.