| 3318_1 - NEMA-17 Bipolar 26.85:1 Planetary Gearbox Stepper |
Product Features
- 26 103/121 : 1 Planetary Gearbox, High Torque
- 0.067° Step Angle
- Gearbox rated for sustained torque of 30 kg-cm
- NEMA-17 Bipolar 4-wire
Approximate arrival date of new stock: June 7, 2013
This NEMA-17 motor has an integrated Planetary gearbox with a 26 103/121 :1 ratio. At 1.68 Amps (maximum current), this gearbox stepper can produce a maximum torque of 77 kg-cm. However, the gearbox is only rated for 30 kg-cm of continuous torque, and 80 kg-cm for brief overloads. Loading this gearbox stepper beyond the torque rating of the gearbox will shorten its useful life.
When connected to a 1063 - PhidgetStepper Bipolar 1-Motor, the 3318 has a maximum speed of a little under 23 RPM. At the output of the gearbox, the step angle is a little under 0.07°. When using the step angle in calculations, you should derive the exact step angle by dividing 1.8° by the gearbox reduction ratio.
This particular revision of the 3318 is made by a different manufacturer, but should behave very similarly to the revision 0 version.
The 3318 stepper motor connects to a bipolar motor controller:
The following table shows how to connect the motor wires to the board connectors to produce a clockwise rotation in the stepper motor when increasing position. To wire for counter-clockwise rotation when increasing position, reverse the red and blue wires.
| Wire Color | Black | Green | Red | Blue |
| Board Connector | A | B | C | D |
Note: Make sure to unplug the power cord from the motor controller before switching wires around.
|
Connecting the motor directly to a power supply will destroy the motor and void the warranty. If you want to check your motor make sure it is connected to a constant current / chopper drive controller. |
Motor Properties
| Motor Type | Bipolar Stepper |
| Manufacturer Part Number | 42STH38-1684A |
| Step Angle | 0.067° |
| Step Accuracy | 5 % |
| Holding Torque | 30 kg·cm |
| Rated Torque | 30 kg·cm |
| Maximum Speed (w/1063 Motor Controller) | 22 RPM |
| Maximum Speed (w/1067 Motor Controller) | 174 RPM |
| Acceleration at Max Speed (w/1067 Motor Controller) | 600000 1/16 steps/sec² |
Electrical Properties
| Recommended Voltage | 12 V DC |
| Rated Current | 1.7 A |
| Coil Resistance | 1.7 Ω |
Physical Properties
| Shaft Diameter | 8 mm |
| Mounting Plate Size | NEMA - 17 |
| Weight | 503 g |
| Number of Leads | 4 |
| Wire Length | 300 mm |
Gearbox Properties
| Gearbox Type | Planetary |
| Gear Ratio | 26 103⁄121 : 1 |
| Backlash Error | 1 1⁄2° |
| Maximum Strength of Gears | 30 kg·cm |
| Shaft Maximum Axial Load | 49.1 N |
| Shaft Maximum Radial Load | 98.1 N |
