# Waveshare ST3025 Servo 40 kg·cm 12 V

> Waveshare ST3025 serial bus servo: 40 kg·cm (3.92 N·m) locked-rotor torque at 12 V, 85 rpm no-load, 6–12.6 V input, metal case, brushless motor, steel gears, 1.5 A rated current, 12-bit 360° magnetic encoder, servo / speed-loop motor / step modes, TTL bus to 1 Mbps with up to 253 IDs, current and temperature feedback, 40 × 20 × 40 mm.

- Manufacturer: Waveshare
- Part number: ST3025
- Category: Actuators
- Canonical page: https://www.xirkit.io/products/waveshare-st3025-servo-40-kg-cm-12-v-c282
- Structured JSON: https://www.xirkit.io/products/waveshare-st3025-servo-40-kg-cm-12-v-c282/data.json
- Source: Xirkit structured parts catalog — every value traced to a cited document; unknowns are explicit.

## Key specifications

| Property | Value |
| --- | --- |
| Actuator type | smart_servo |
| Peak torque | 3.923 N·m |
| No-load speed | 85 rpm |
| Rated voltage | 12.6 V |
| Rated current | 1.5 A |
| Torque constant Kt | 0.883 N·m/A |
| Encoder | 360° magnetic, 12-bit (4096 per turn) |
| Control interface | TTL |
| Control modes | position (angle servo mode), speed closed-loop (motor mode), step |
| Dimensions | 40 × 20 × 40 mm |

## Where to buy

| Supplier | Price | Stock | Checked | URL |
| --- | --- | --- | --- | --- |
| www.waveshare.com | 79.99 USD | in_stock | 2026-10-01 | https://www.waveshare.com/st3025-servo.htm |

## FAQ

**What voltage powers the Waveshare ST3025 Servo 40 kg·cm 12 V?**

Supply range 6–12.6 V.

**How much does the Waveshare ST3025 Servo 40 kg·cm 12 V cost?**

From $79.99 at www.waveshare.com. Prices are observed unit prices before tax and shipping.

**What are the Waveshare ST3025 Servo 40 kg·cm 12 V dimensions?**

40 × 20 × 40 mm. A STEP model is available for enclosure fit checks.

**Where does this Waveshare ST3025 Servo 40 kg·cm 12 V data come from?**

Every value in this record is traced to a source — 2 documents including the board and chip datasheets — with the page and table cited per value. Unknowns are left explicit, never guessed.

## Sources

- [Waveshare ST3025 Servo 40 kg·cm 12 V datasheet](https://www.waveshare.com/st3025-servo.htm)
- [www.waveshare.com listing](https://www.waveshare.com/st3025-servo.htm)

## Part graph

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