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KST X15-855X HV Mini Digital Metal Gear Brushless Tail Servo 15Kgf.cm 0.05sec
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KST X15-855X HV Mini Digital Metal Gear Brushless Tail Servo 15Kgf.cm 0.05sec
The KST X15-855X HV Mini Digital Metal Gear Brushless Tail Servo is a mini tail servo for RC helicopters that need fast response in a compact 15mm-class case. KST positions it for helicopters in the 430mm-570mm rotor blade range and other RC applications where the size, torque, and speed ratings fit the installation.
Verified KST data lists a DC 6.0V-8.4V voltage range, up to 15Kgf.cm torque at 8.4V, and 0.05sec/60deg speed at 8.4V. The technical PDF also lists the same torque steps as 1.0N.m / 1.3N.m / 1.5N.m.
With a 35.5 x 15 x 35.5mm case, 25T 6mm output spline, brushless motor, hardened steel gears, and about 45g weight, X15-855X is built for precise HV tail control in compact helicopter setups.
Product Images
Features
- 15Kgf.cm peak torque - KST page data lists 15Kgf.cm at 8.4V; the PDF lists 1.5N.m at 8.4V.
- 0.05sec fast tail response - Listed speed reaches 0.05sec/60deg at 8.4V.
- Mini 15mm-class case - Compact 35.5 x 15 x 35.5mm dimensions fit many mini helicopter layouts.
- 430mm-570mm helicopter focus - KST positions it for helicopters in this rotor blade size range.
- Brushless DC motor - Supports efficient high-speed tail output.
- Hardened steel gears - Adds drivetrain durability for tail linkages.
- CNC-style aluminum case - Provides a rigid mini-servo housing.
- 25T 6mm output spline - Uses the listed spline for compatible servo horns.
- 2BB construction - Dual ball bearings support the output train.
- 760us/560Hz signal format - Tail-servo command format listed in KST data.
Specifications
| Parameter | Value |
|---|---|
| Model | KST X15-855X |
| Shopify SKU | KST-X15-855X |
| Rated Voltage | DC 7.4V |
| Voltage Range | DC 6.0V-8.4V |
| Torque | 10Kgf.cm / 1.0N.m @ 6.0V; 13Kgf.cm / 1.3N.m @ 7.4V; 15Kgf.cm / 1.5N.m @ 8.4V |
| Speed | 0.07sec/60deg @ 6.0V; 0.06sec/60deg @ 7.4V; 0.05sec/60deg @ 8.4V |
| Working Frequency | 760us / 560Hz |
| Command Interface | PWM command; pulse length 450us-1050us |
| Output Shaft Spline | 25T, 6mm |
| Case Material | Aluminum alloy |
| Motor Type | Brushless DC motor |
| Gear Set Material | Hardened steel |
| Position Sensor | Potentiometer |
| Ball Bearing | 2BB |
| Case Dimensions | 35.5 x 15 x 35.5mm +/-0.2mm |
| Weight | 45g +/-10% |
| Temperature Range | -10C to +65C |
Reference Documents
Application
- 430mm-570mm RC helicopter tail control - KST positions X15-855X for this rotor blade size range.
- Mini helicopter upgrades - Useful when a compact HV tail servo is needed.
- High-speed yaw response - Supports installations that require the listed 0.05sec/60deg response.
- HV receiver systems - Works within the listed DC 6.0V-8.4V range when powered correctly.
- 760us tail-servo systems - Fits control systems configured for 760us/560Hz PWM command format.
- Custom compact mechanisms - Can be used outside RC helicopters after confirming load, voltage, signal, and travel.
Packing List
| Description | Quantity |
|---|---|
| KST X15-855X tail servo | 1 |
| CNC servo horn | 1 |
| Plastic servo horn | 1 |
| Servo horn screw | 1 |
| Mounting screw | 4 |
| Rubber grommet | 4 |
| Eyelet | 4 |
FAQ
How does X15-855X compare with X20-1035?
X15-855X is a mini 15mm-class tail servo for 430mm-570mm rotor blade helicopters, while X20-1035 is a larger X20 tail servo for 500-800 class helicopters.
Does OpenELAB list multiple Shopify variants for this product?
No. The current Shopify product is a single variant with SKU KST-X15-855X.
What is the maximum listed torque?
KST page data lists 15Kgf.cm at 8.4V; the technical PDF lists 1.5N.m at 8.4V.
What is the fastest listed speed?
The fastest listed speed is 0.05sec/60deg at 8.4V.
What voltage range does it support?
The listed voltage range is DC 6.0V-8.4V.
What is included in the package?
KST lists one X15-855X tail servo, one CNC servo horn, one plastic servo horn, one servo horn screw, four mounting screws, four rubber grommets, and four eyelets.
What spline does it use?
The technical specification lists a 25T, 6mm output shaft spline.
What should I check before installation?
Confirm the 35.5 x 15 x 35.5mm case, 25T 6mm spline, 760us/560Hz signal setup, HV supply, and tail linkage clearance.
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