Several places list this motor in the ~ $50 USD range.
Applied Motion HT17 [
www.mouser.com] [
us.misumi-ec.com] [
www.walkeremd.com]
The first google result for NEMA17 stepper is a ROB-10846 for $17 and seems to outperform the HT17 in several regards. [
www.sparkfun.com]
Why is there such a drastic price difference between these motors?
HT17:
Part Number HT17-277
Frame Size NEMA 17
Motor Type High torque
Part Number w/Double Shaft HT17-277D
Part Number w/Encoder HT17-277D-WAA
Part Number w/Encoder & Cover NA
Motor Length 1.90 inches
Number of Lead Wires 8
Lead Wire Configuration flying leads, no connector
Lead Wire/Cable Length 12 inches
Lead Wire Gauge 26 AWG
Unipolar Holding Torque 43.9 oz-in
Bipolar Holding Torque 62.3 oz-in
Step Angle 1.8 deg
Bipolar Series Current 0.28 A/phase
Bipolar Series Resistance 60.0 Ohms/phase
Bipolar Series Inductance 128 mH/phase
Bipolar Parallel Current 0.57 A/phase
Bipolar Parallel Resistance 15.0 Ohms/phase
Bipolar Parallel Inductance 32.0 mH/phase
Unipolar Current 0.40 A/phase
Unipolar Resistance 30.0 Ohms/phase
Unipolar Inductance 32.0 mH/phase
Rotor Inertia 1.16E-03 oz-in-sec2
Integral Gearhead No
Weight 0.8 lbs
Storage Temperature -30 to 70 °C
Operating Temperature -20 to 50 °C
Insulation Class Class B (130 ºC)
Maximum Radial Load NA
Maximum Thrust Load NA
Shaft Run Out 0.001 inch T.I.R. max
Radial Play 0.001 inch max w/ 1.1 lb load
End Play 0.003 inch max w/ 1.1 lb load
Perpendicularity 0.004 inches
Concentricity 0.002 inches
ROB-10846:
68 oz.in
400 steps/rev
Bipolar
Step Angle (degrees) : 0.9
2-Phase
Rated Voltage: 3V
Rated Current: 1.7A/Phase
5mm Diameter Drive Shaft
Holding Torque: 48N.cm
NEMA 17 form factor
