
Overview
The CHIHAI MOTOR CHW-GW 12T-N 20VA DC gear motor combines a compact brushed motor with worm reduction and two opposed D-shaped output shafts. Choose the package, ratio/frame and 6 V or 12 V winding. Motor-only, mini PWM control, EMC solder-free board, power-adapter and bracket packages are distinct configurations.
Features
- Two opposed 3 mm D output shafts for compact mechanisms.
- Metal gears and copper rotor windings.
- Compact worm reduction and self-locking behavior for suitable applications; do not treat it as a safety brake or a certified holding-torque device.
- Six standard ratios plus a separately identified 603: 1 steel-plate-frame option.
- Optional plug-in EMC terminal board avoids soldering directly to the motor tabs.
- Motor polarity can be reversed after stopping for opposite rotation.
Specifications
| Brand / model | CHIHAI MOTOR / CHW-GW 12T-N 20VA |
| Mechanism | Permanent-magnet brushed DC motor with worm and metal gear reduction, two opposed output shafts |
| Voltage | 6 V or 12 V as selected; no 3 V retail option in this listing |
| Output shafts | Each Ø3 mm D shaft, upper 0 / lower-0.03 mm; flat dimension 2.5 mm upper 0 / lower-0.05 mm |
| Shaft projection / flat length | Each projection 10.0±0.3 mm; flat length 9.2 mm upper+0.03 / lower 0 |
| Front references | Ø4 mm shoulder; 0.5 mm reference at each gearbox side; 10 mm gearbox width |
| Mounting drawing | Two Ø1.4 mm holes, 8.50 mm spacing, 4.0 mm top reference |
| Housing / motor references | 12 mm gearbox-front width, 18 mm gear section, 15.2 mm motor section, 33.5 mm MAX overall; 1.75 mm top reference |
| Rear / body references | 1.0 mm rear projection,Ø4 mm rear feature; 7.3 mm reference andØ12.1 mm MAX motor width |
| Net mass | Approximately 14 g motor reference; shipping weight is an independent estimate |
| Frame selections | Standard ratios 42/118/236/302/603/1030: 1, plus a distinct 603: 1 steel-plate-frame option |
| EMC board option | Solder-free terminal board with matching plug-in lead; no encoder included |
| Mini controller | DC 2.2–12.0 V supply, 1.8–12 V adjustable reference, current below 2 A |
| Controller hardware | RV 097NS switched potentiometer, 7 mm panel opening, 2 A resettable fuse, LED indicator, screw terminals |
Voltage-Specific Performance
Use the table for the selected voltage and standard ratio. No-load speed, rated speed, rated torque and stall torque are separate operating points. The 603: 1 steel-plate-frame option has no separate performance curve here; do not assume every standard 603: 1 figure is independently verified for that frame.
12 V standard-frame references
Input power 1.02 W; no-load current 30 mA; rated current 85 mA; stall current 700 mA.
| Ratio : 1 | No-load rpm | Rated gf.cm | Rated rpm | Stall gf.cm |
|---|---|---|---|---|
| 42 | 381 | 71 | 333 | 235.2 |
| 118 | 136 | 142 | 119 | 472 |
| 236 | 68 | 283 | 59 | 944 |
| 302 | 53 | 362 | 46 | 1208 |
| 603 | 27 | 579 | 23 | 1929 |
| 1030 | 16 | 989 | 14 | 3296 |
6 V standard-frame references
Input power 0.36 W; no-load current 20 mA; rated current 60 mA; stall current 350 mA.
| Ratio : 1 | No-load rpm | Rated gf.cm | Rated rpm | Stall gf.cm |
|---|---|---|---|---|
| 42 | 190 | 22 | 143 | 73.5 |
| 118 | 68 | 62 | 51 | 206.5 |
| 236 | 34 | 124 | 25 | 413 |
| 302 | 26 | 159 | 20 | 528.5 |
| 603 | 13 | 317 | 10 | 1055.3 |
| 1030 | 8 | 541 | 6 | 1802.5 |
Stall values are not continuous operating ratings. Select by the rated load point and avoid overload or sustained stall. Lower drive voltage and speed can change available torque. The two shafts are opposed ends of the output arrangement, not two independently controlled motors.
Mechanical Fit
The original engineering-view segments below preserve geometry and numeric references. Check both shaft ends, mounting holes, frame clearance and the chosen bracket. A 9.2 mm D-flat length is different from the 10.0±0.3 mm shaft projection. The steel-plate 603: 1 selection remains a separate construction choice; the standard-frame illustration is a fit reference rather than proof of identical load capability.
Power, Controller and EMC Board
6 V motor and 12 V adapter packages require special care: a 12 V adapter must not be connected directly to a 6 V motor. Use a properly rated regulated 6 V stage before the 6 V motor. The included mini PWM speed controller is not a guaranteed 12 V-to-6 V voltage regulator. If you need direct use of the included 12 V adapter, select a 12 V motor configuration.
The mini controller accepts DC 2.2–12.0 V and lists a 1.8–12 V adjustable reference. Keep current below 2 A and within the selected motor rating. The RV 097NS potentiometer includes an on/off switch and a 7 mm panel opening. A 2 A resettable fuse, LED indicator and screw terminals are provided. Follow actual board markings for supply and motor connection; DC only. Do not connect mains to the DC motor or controller. Electronic reversing is not promised by this mini speed-control board.
The optional EMC solder-free board provides a plug-in terminal connection with the pictured matching lead and avoids soldering heat at the motor terminals. It is not a Hall encoder or feedback controller. Its interference-control function is not an EMC certification claim. Reversing motor polarity reverses motor direction; verify the exact board and harness orientation before connection.
What's Included
| Package | Contents |
|---|---|
| Motor Only | One selected motor plus only the accessories named in the package |
| Motor + Mini PWM Controller | One selected motor plus only the accessories named in the package |
| Motor + EMC Solder-Free Board | One selected motor plus only the accessories named in the package |
| EMC Board Motor + Mini PWM Controller | One selected motor plus only the accessories named in the package |
| Motor + 12 V Power Adapter | One selected motor plus only the accessories named in the package |
| Motor + 12 V Adapter + Mini PWM Controller | One selected motor plus only the accessories named in the package |
| EMC Board Motor + 12 V Adapter + Mini PWM Controller | One selected motor plus only the accessories named in the package |
| Motor + Plastic Bracket | One selected motor plus only the accessories named in the package |
| Motor + Green Bracket | One selected motor plus only the accessories named in the package |
EMC board packages include the pictured board and matching lead. Power-adapter packages include one 12 V adapter; 6 V motor combinations need an additional suitable regulated 6 V stage that is not included. Bracket choices supply one pictured plastic or green bracket respectively. Package images are alternatives, not multiple motors in a single purchase. A complete robot, encoder, feedback controller and mechanism are not included. Power-adapter mains plug type and input range are not specified here; confirm local compatibility before use.
Applications
Compact robot mechanisms, small robotic hands, smart-home mechanisms, automatic pet-feeding development and miniature camera platforms where the selected load, speed, shaft fit and power system meet the design requirements.
Installation and Operation
Match nominal motor voltage and confirm wiring before energizing. Keep mounting hardware clear of the gears and both output shafts. Avoid frequent rapid reversals, overload and sustained stall. Do not force the shafts to turn while unpowered or rely on worm self-locking for a safety-critical holding function. Noise and speed vary with load and reduction.
FAQ
Can the 12 V adapter power a 6 V motor directly?
No. Use a properly rated regulated 6 V stage, or choose the 12 V motor for direct adapter operation. PWM speed control alone is not a guaranteed voltage regulator.
Does the EMC board measure rotation?
No. It is a solder-free connection/interference-control board, not an encoder.
Is 603: 1 steel-plate frame the same option as standard 603: 1?
No. They are separate construction selections; only the standard-frame performance reference is provided.
Are the two shafts independently driven?
No. They belong to one motor and output arrangement.
Visual Details








