Motor quotes stall when the inquiry is a paragraph of adjectives. Three numbers move a drivetrain from idea to proposal in one email.
1. Torque — the honest load
Power ratings flatter; torque tells the truth. Quote the real load torque at the shaft — including gearing — plus the breakaway needed to start it. Oversizing a motor oversizes the drive, the cabling and the invoice.
2. Speed range — where the work happens
A motor that idles at base speed and a motor that grinds all day at 20% speed are different thermal problems wearing the same frame. State the working range, not just the maximum.
3. Duty cycle — how hard, how often
Ten starts a day and six hundred are different machines. Duty decides rotor design, insulation class and whether the brake sees service or abuse — say how the axis will actually run.
Then the environment
Ambient temperature, altitude, dust, washdown, atmosphere: one line about the room often changes the enclosure — and saves a warranty claim later.
