Servo selection: torque, speed, gears and voltage
How to select servos for trainers, sport aircraft, large models, cars and boats without under-sizing a control surface.
X20-7.4-M-820 Brushless HLS 6BB Servo 30Kgf.cm 0.09sec for RC Helicopters
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Contact RC-MODEL for current availability, technical fit, compatible accessories and a formal quote.
X20-7.4-M-820 Brushless HLS 6BB Servo 30Kgf.cm 0.09sec for RC Helicopters is a KST Servos product selected for Car Servos, Helicopter Servos. This page is written for practical buying decisions, with the key fit, size, voltage and performance details organized in one place.
Use it to compare torque, speed, voltage range, construction, dimensions, weight, variants and accessory compatibility before choosing the right component for an RC aircraft, helicopter, car, glider, UAV or workshop installation.
Key Advantages
- Brushless DC Motor
- Hardened Steel Gears
- Contactless Sensor
- Extreme Torque and Excellent Speed
- CNC Aluminium Case
- 6 Ball Bearings
Core Specifications
- Voltage Range: DC6.0V-8.4V
- Rated Voltage: DC7.4V
- Stalling Torque: 30Kgf.cm@7.4V
- No-load Speed: 0.09sec/60°@7.4V
- Motor Type: Brushless DC Motor
- Gear Set Material: Hardened Steel (HLS)
- Ball Bearing: 6 BB
- Case Dimensions: 40mm*20mm*40mm±0.2mm
- Weight: 75g±10%
- Item: X20-7.4-M-820 HV Servo
- Rated Torque: 7Kgf.cm@7.4V
- Stalling Current: 4.95A
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| Technical Specifications | |
| Manufacturer | KST Servos |
| Brand | KST |
| Product Code | BR0023.0154-1 |
| All Variant SKUs | BR0023.0154-1 |
| Rated Voltage | DC7.4V |
| Voltage Range | DC6.0V-8.4V |
| Stalling Torque | 30Kgf.cm@7.4V |
| No-load Speed | 0.09sec/60°@7.4V |
| Working Frequency | 1520μs/333Hz |
| Default Travel Angle | ± 100°=200° Total When 500μs-2500μs |
| Temperature Range | -10℃……+65℃ |
| Case Material | Aluminium Alloy |
| Motor Type | Brushless DC Motor |
| Gear Set Material | Hardened Steel (HLS) |
| Position Sensor | Contactless |
| Ball Bearing | 6 BB |
| Case Dimensions | 40mm*20mm*40mm±0.2mm |
| Weight | 75g±10% |
| KST Collections | Helicopter Servos, Car Servos, Industrial, Standard Servos, X Series |
| Series | X Series |
| Size Class | Standard Servos |
| Application | Car Servos, Helicopter Servos |
| Features | Brushless DC Motor; Hardened Steel Gears; Contactless Sensor; Extreme Torque and Excellent Speed; CNC Aluminium Case; 6 Ball Bearings |
| Package Includes | 1 * X20-7.4-M-820 Standard Servo; 1 Pack of Accessories; Download; X20-7.4-M-820 Servo Technical Specification |
| Item | X20-7.4-M-820 HV Servo |
| Product Type | RC |
| Rated Torque | 7Kgf.cm@7.4V |
| Rated Speed | 0.17sec/60°@7.4V |
| Rated Current | 1.25A |
| Stalling Current | 4.95A |
Tags: KST Servos, BR0023.0154-1, Helicopter Servos, Car Servos, Industrial & UAV Servos, Standard Servos, X Series, RC servo