# Stepper Motor, NEMA17, 1.7A, 1.8°, 42x42x40mm, Bipolar

> Nema17 stepper motor, phase current 1.7A, 1.8 degree step angle, 2 phases, holding torque 40N.cm, detent torque 2.2N.cm, recommended voltage 12VDC, dimensions 42x42x40mm. Compatible with A4988 and DRV8825 drivers, used to drive axes in 3D printers and CNC routers.

- Page: https://sigmanortec.ro/en/stepper-motor-nema17-17a-18-degrees-42x42x40mm
- Price: 57.92 RON
- Availability: In stock; 1-2 zile
- Reference: 22076 · EAN: 5948209717723
- Category: Mechatronics and IoT > Moving step by step
- Specifications: Nominal Current: 1.7 A
- Package (shipping data): 0.285 kg
- Updated: 2026-10-17
- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Prices: RON, VAT included; prices and stock as of 2026-10-22 04:49 (Europe/Bucharest)

## Description

Stepper motor for precise axis drive on 3D printers and CNC routers, compatible with A4988 and DRV8825 drivers. Offers 1.8 degree step for fine control, 1.7A current per phase with 2 phases for stable torque, 40N.cm holding force for secure positioning, compact 42x42x40mm format suitable for integration into standard assemblies.
The NEMA 17 JK42HS40-1704 stepper motor is a 2-phase bipolar hybrid motor. It is used for moving axes on 3D printers, CNC routers, laser engravers, and other linear positioning systems. It has a step angle of 1.8 degrees, meaning 200 steps per revolution, and a holding torque of 4.2kg.cm (approx. 41N.cm). This provides precise and repeatable motion, without position sensors.
The body is 39.5mm long and has a standard NEMA 17 flange measuring 42.3 x 42.3mm. The flange has 4 threaded M3 holes spaced 31mm apart and a 22mm centering collar, so the motor fits most mounts and parts for 3D printers and CNC machines. The shaft has a diameter of 5mm and a length of 24mm. It is suitable for GT2 pulleys, 5 x 8mm flexible couplings for T8 lead screws, or extruder mechanisms. The motor has 4 UL1007 AWG26 wires with a minimum length of 500mm.
The rated current is 1.7A per phase, and the coil resistance is low (1.5Ω). Therefore, the motor is used with current-controlled drivers such as A4988, DRV8825, TMC2208, or TMC2209, powered at 12 - 24VDC. It is compatible with Arduino Uno with CNC Shield V3 and Arduino Mega with RAMPS 1.4. It also works with 3D printer boards running Marlin or Klipper firmware, with GRBL controllers, and with ESP32, STM32, or Raspberry Pi platforms, through a driver.
Specifications:
Model: JK42HS40-1704
Motor type: 2-phase bipolar hybrid
Step angle: 1.8 degrees (200 steps/revolution)
Rated phase current: 1.7A
Rated phase voltage: 2.55V
Phase resistance: 1.5Ω ±10% (at 20°C)
Phase inductance: 2.3mH ±20% (1kHz, 1V RMS)
Holding torque: 4.2kg.cm (approx. 41N.cm)
Insulation class: B (130°C)
Temperature rise: max. 80K at rated current
Number of wires: 4 (UL1007 AWG26)
Wire length: min. 500mm
Recommended driver supply voltage: 12 - 24VDC
Body dimensions: 42.3 x 42.3 x 39.5mm
Shaft: Ø5mm x 24mm, with flat, D-shape
Centering collar: Ø22mm x 2mm
Mounting holes: 4 x M3 x 0.5, min. depth 4.5mm, spacing 31mm
Weight: 0.24kg
Pinout:
Wire
Color
Function
A4988 Pin
DRV8825 Pin
A
Black
Coil 1 (A+)
1A
A1
C
Green
Coil 1 (A-)
1B
A2
B
Red
Coil 2 (B+)
2A
B1
D
Blue
Coil 2 (B-)
2B
B2
Step Sequence:
Full-step command sequence, viewed from the flange side. Steps 1 to 4 give clockwise direction (CW), and steps 4 to 1 give counterclockwise direction (CCW).
Step
A
B
C
D
1
+
2
+
3
+
4
+
Dimensions:
Usage:
Mount the motor on a bracket with 4 M3 screws. Choose the screw length so that they do not enter more than 4.5mm into the motor body.
Attach the GT2 pulley, coupling, or extruder gear to the shaft and tighten the locking screw firmly.
Identify the coil pairs. The black and green wires form coil 1, and the red and blue wires form coil 2. If in doubt, measure with a multimeter: between the ends of the same coil you should read approx. 1.5Ω.
Connect coil 1 to outputs 1A and 1B (A4988) or A1 and A2 (DRV8825). Connect coil 2 to 2A and 2B (A4988) or B1 and B2 (DRV8825).
Adjust the driver current limit using the potentiometer before first startup. For the DRV8825, use the formula Vref = I / 2. For the A4988, the formula is Vref = I x 8 x Rs, so for Rs = 0.1Ω (R100 marking) the result is Vref = I x 0.8. For continuous operation, 1.2 - 1.5A is recommended, without exceeding 1.7A.
Power the driver at 12 - 24VDC from a supply that can provide the required current for all motors. Install a capacitor of at least 100uF on the driver power supply.
Connect the STEP, DIR, and EN pins of the driver to the control board (Arduino, ESP32, STM32, or 3D printer board).
Set the number of steps per revolution in firmware: 200 for full-step, 3200 for 1/16 microstep (A4988), or 6400 for 1/32 microstep (DRV8825).
Do not connect or disconnect the motor while the driver is powered, as the driver may be damaged.
If the motor rotates in the wrong direction, reverse the wires of one coil or change the direction in firmware. If the motor vibrates without rotating, check the coil pairs.
It is normal for the motor to heat up during operation, with its temperature potentially rising by up to 80 degrees above ambient. Ensure good ventilation and reduce the current if the motor becomes too hot.