# Stepper Motor: Bipolar, 200 Steps/Rev, 20×30mm, 3.9V, 0.6 A/Phase

**Type:** Product page · **SKU:** POLOLU-1204 · **Brand:** [Pololu](https://core-electronics.com.au/brands/pololu-australia)
**Page:** https://core-electronics.com.au/stepper-motor-bipolar-200-steps-rev-20-30mm-3-9v-0-6-a-phase.html ([markdown](https://core-electronics.com.au/stepper-motor-bipolar-200-steps-rev-20-30mm-3-9v-0-6-a-phase.html.md))

This small NEMA 8-size hybrid bipolar stepping motor has a 1.8° step angle (200 steps/revolution). Each phase draws 600 mA at 3.9 V, allowing for a holding torque of 180 g-cm (2.5 oz-in). With a weight of 60 g, this is one of the smallest stepper motors Pololu carry.

## Pricing

- **Price:** $91.95 (inc GST) — $83.59 AUD, exc GST
- **Quantity discounts:** 6+ $80.25 (exc GST) · 12+ $77.74 (exc GST)

## Availability & dispatch

- Available with a lead time — expect dispatch between Aug 31 and Sep 01.

## Description

| [![](https://core-electronics.com.au/attachments/localcontent/0J2286_1892927f0cd.jpg)](https://core-electronics.com.au/attachments/localcontent/0J2286_1641576afb9.jpg) |
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| Bipolar stepper motor wires are terminated with bare leads. |

| ![](https://core-electronics.com.au/attachments/localcontent/0J2296_2723a56f97.gif) |
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| Bipolar stepper motor wiring diagram. |

This small hybrid bipolar stepping motor has a 1.8° step angle (200 steps/revolution). Each phase draws 600 mA at 3.9 V, allowing for a holding torque of 180 g-cm (2.5 oz-in). The motor has four color-coded wires terminated with bare leads: black and green connect to one coil; red and blue connect to the other. These leads connect to the stepper motor through a removable JST-ZHR-5 connector. The motor can be controlled by a pair of suitable H-bridges (one for each coil), but Pololu recommend using a [bipolar stepper motor driver](https://core-electronics.com.au/breakout-boards-and-modules/motor-drivers-controllers/stepper-motor-drivers.html) or one of Pololu's [Tic Stepper Motor Controllers](https://core-electronics.com.au/breakout-boards-and-modules/motor-drivers-controllers/stepper-motor-drivers.html). In particular, the Tics make control easy because they support six different interfaces (USB, TTL serial, I²C, RC, analog voltages, and quadrature encoder) and are configurable over USB with Pololu's free configuration utility.

Pololu's [4 mm universal mounting hub](https://core-electronics.com.au/pololu-universal-aluminum-mounting-hub-for-4mm-shaft-4-40-holes-2-pack.html) can be used to mount objects on the stepper motor’s 4 mm-diameter output shaft. For a slightly more powerful motor in the same NEMA size but a longer length, consider [Stepper Motor: Bipolar, 200 Steps/Rev, 20×42mm, 4.3V, 0.8 A/Phase](https://core-electronics.com.au/stepper-motor-bipolar-200-steps-rev-20-42mm-4-3v-0-8-a-phase.html). A comparison between these two motors can be seen in the image below.

| [![](https://core-electronics.com.au/attachments/localcontent/0J11420_182436abd35.jpg)](https://core-electronics.com.au/attachments/localcontent/0J11420_53692f64bf8.jpg) |
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| [SY20STH30-0604A](https://core-electronics.com.au/stepper-motor-bipolar-200-steps-rev-20-30mm-3-9v-0-6-a-phase.html) (top) and [SY20STH42-0804A](https://core-electronics.com.au/stepper-motor-bipolar-200-steps-rev-20-42mm-4-3v-0-8-a-phase.html) (bottom). |

**Specifications**

- Size: 20 mm square × 30 mm, not including the shaft (NEMA 8)
- Weight: 60 g (2 oz)
- Shaft diameter: 4 mm “D”
- Steps per revolution: 200
- Current rating: 600 mA per coil
- Voltage rating: 3.9 V
- Resistance: 6.5 O per coil
- Holding torque: 180 g-cm (2.5 oz-in)
- Inductance: 1.7 mH per coil
- Lead length: 30 cm (12")
- Output shaft supported by two ball bearings

More specifications are available in the datasheet (51k pdf).

**Dimensions**

The following diagram shows the stepper motor dimensions in mm. The dimension labeled “Length” is 30 mm. The output D-shaft has a length of 15 mm and a 4 mm diameter with a section that is flattened by 0.5 mm. This shaft works with Pololu's [4 mm universal mounting hub](https://core-electronics.com.au/pololu-universal-aluminum-mounting-hub-for-4mm-shaft-4-40-holes-2-pack.html).

| ![](https://core-electronics.com.au/attachments/localcontent/0J2287_247038e69f4.jpg) |
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| [![](https://core-electronics.com.au/attachments/localcontent/0J2297_3186898a777.jpg)](https://core-electronics.com.au/attachments/localcontent/0J2297_246528185f4.jpg) |
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| The inside of a bipolar stepper motor (SOYO NEMA 14-size). |

**Stepper Motor Applications**

Stepper motors are generally used in a variety of applications where precise position control is desirable and the cost or complexity of a feedback control system is unwarranted. Here are a few applications where stepper motors are often found:

- Printers
- CNC machines
- 3D printer/prototyping machines
- Laser cutters
- Pick and place machines
- Linear actuators
- Hard drives

| ![](https://core-electronics.com.au/attachments/localcontent/0J4511_6816439839d.jpg) |
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| Pololu’s assortment of stepper motors. |

**Note:** This stepper motor is SOYO part number SY20STH30-0604A.

**People often buy this product together with:**

| [![Pololu Universal Aluminum Mounting Hub for 4mm Shaft, #4-40 Holes (2-Pack)](https://core-electronics.com.au/attachments/localcontent/0J1106_30989f4660.jpg)](https://core-electronics.com.au/pololu-universal-aluminum-mounting-hub-for-4mm-shaft-4-40-holes-2-pack.html) | [Pololu Universal Aluminum Mounting Hub for 4mm Shaft, #4-40 Holes (2-Pack)](https://core-electronics.com.au/pololu-universal-aluminum-mounting-hub-for-4mm-shaft-4-40-holes-2-pack.html) |
|---|---|

| [![A4988 Stepper Motor Driver Carrier](https://core-electronics.com.au/attachments/localcontent/0J10064_4074c7c4a6.jpg)](https://core-electronics.com.au/a4988-stepper-motor-driver-carrier.html) | [A4988 Stepper Motor Driver Carrier](https://core-electronics.com.au/a4988-stepper-motor-driver-carrier.html) |
|---|---|

| [![Stepper Motor: Bipolar, 200 Steps/Rev, 28×32mm, 3.8V, 0.67 A/Phase](https://core-electronics.com.au/attachments/localcontent/0J2281_372101817e.jpg)](https://core-electronics.com.au/stepper-motor-bipolar-200-steps-rev-28-32mm-3-8v-0-67-a-phase.html) | [Stepper Motor: Bipolar, 200 Steps/Rev, 28×32mm, 3.8V, 0.67 A/Phase](https://core-electronics.com.au/stepper-motor-bipolar-200-steps-rev-28-32mm-3-8v-0-67-a-phase.html) |
|---|---|

**Dimensions**

 | Size: | 20 mm square × 30 mm[1](https://core-electronics.com.au/#note1) |
|---|---|
| NEMA size: | 8 |
| Weight: | 60 g |
| Shaft diameter: | 4 mm |

**General specifications**

 | Shaft type: | 4 mm "D" |
|---|---|
| Current rating: | 600 mA[2](https://core-electronics.com.au/#note2) |
| Voltage rating: | 3.9 V |
| Holding torque: | 2.5 oz·in |
| Steps per revolution: | 200 |
| Resistance: | 6.5 Ohm[2](https://core-electronics.com.au/#note2) |
| Inductance per phase: | 1.7 mH |
| Number of leads: | 4 |
| Lead length: | 30 cm |

**Notes:**

1Not including the shaft.2Per coil. **File downloads**

- **SY20STH30-0604A stepper motor datasheet (51k pdf)**
- **3D model of the SY20STH30-0604A stepper motor (Pololu item #1204) (3MB step)**

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/s/t/stepper_motor_bipolar_200_steps_rev_20x30mm_3.9v_0.6_a_phase__pololu_1204__00.jpg)