1. Safety Information
Please read the ENTIRE instruction manual to become familiar with the features of the product before operating. Failure to operate the product correctly can result in damage to the product, personal property, and cause serious injury.
This is a sophisticated hobby product. It must be operated with caution and common sense and requires some basic mechanical ability. Failure to operate this product in a safe and responsible manner could result in injury or damage to the product or other property. This product is not intended for use by children.
Do not use with incompatible components or alter this product in any way outside of the instructions provided by Horizon Hobby, LLC. This manual contains instructions for safety, operation, and maintenance. It is essential to read and follow all the instructions and warnings in the manual, prior to assembly, setup or use, in order to operate correctly and avoid damage or serious injury.
2. Product Overview
The ARRMA BLX120 120A waterproof Electronic Speed Controller (ESC) is designed to provide consistent power control for your RC vehicle. It is compatible with 3S and 4S LiPo battery configurations.
Key Features:
- 120A continuous current capability.
- Waterproof design for all-weather operation.
- Equipped with super-reliable EC5 connectors.
- Built-in cooling fan for reduced heat during intense use.
- Over-voltage protection.
- Two-stage LiPo cut-off for enhanced cell management.
- Fitted with 12AWG high-quality wires.
- Integrated 6V BEC (Battery Eliminator Circuit) unit.
- Three-mode throttle profile: Forward/Reverse/Brake.
3. What's in the Box
Upon opening the product packaging, verify that all components are present and undamaged. The package should contain:
- 1 x BLX120 Brushless 4S ESC
- 1 x Loop Connector
4. Setup
Follow these steps to properly install and connect your BLX120 ESC into your RC vehicle:
- Mounting the ESC: Securely mount the BLX120 ESC in your vehicle's chassis using appropriate mounting tape or screws. Ensure it is in a location that allows for adequate airflow to the cooling fan.
- Motor Connection: Connect the three motor wires from the ESC to your brushless motor. The BLX120 uses 4mm bullet connectors. Ensure the connections are firm and correct for proper motor rotation. If the motor spins in the wrong direction, swap any two of the three motor wires.
- Receiver Connection: Plug the ESC's receiver wire (typically a single servo-style connector) into the throttle channel (usually channel 2) of your RC receiver.
- Battery Connection: Connect your 3S or 4S LiPo battery to the ESC's EC5 battery connectors. The BLX120 is equipped with two EC5 connectors for battery input. Ensure correct polarity.
- Power Switch: Mount the power switch in an accessible location on your vehicle.
- Initial Calibration (if required by your radio system): Most ESCs require a one-time calibration with your radio transmitter to set the neutral, full throttle, and full brake points. Refer to your radio system's manual for specific calibration procedures.
5. Operating Instructions
The BLX120 ESC offers a versatile throttle profile and built-in protections for reliable operation:
- Throttle Profile: The ESC supports a three-mode throttle profile: Forward, Reverse, and Brake. This allows for precise control of your vehicle's movement.
- LiPo Cut-Off: The two-stage LiPo cut-off feature protects your LiPo batteries from over-discharge, which can cause permanent damage. The ESC will reduce power or cut off completely when the battery voltage drops below a safe level (3.4V per cell).
- Cooling Fan: The integrated cooling fan automatically activates to dissipate heat from the ESC during operation, especially under heavy loads, maintaining optimal performance and longevity.
- Over-Voltage Protection: The ESC is designed with over-voltage protection, activating if the input voltage exceeds 17.2V, safeguarding the unit from electrical damage.
6. Maintenance
Regular maintenance ensures the longevity and optimal performance of your BLX120 ESC:
- Cleaning: After each use, especially in dusty or wet conditions, gently clean the ESC to remove dirt, dust, and moisture. Use a soft brush or compressed air. Avoid using solvents or harsh chemicals.
- Connection Check: Periodically inspect all electrical connections (battery, motor, receiver) for signs of wear, corrosion, or looseness. Ensure EC5 connectors are clean and securely seated.
- Cooling Fan: Ensure the cooling fan is free from obstructions and spins freely. Clean any debris that may accumulate on or around the fan blades.
- Wire Inspection: Check the 12AWG wires for any nicks, cuts, or exposed insulation. Repair or replace damaged wires immediately to prevent short circuits.
- Storage: When not in use, store the ESC in a dry, cool place away from direct sunlight and extreme temperatures.
7. Troubleshooting
If you encounter issues with your BLX120 ESC, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| ESC blinks red and does not respond. | Low battery voltage (LiPo cut-off activated) or calibration issue. | Charge your battery. Re-calibrate the ESC with your radio transmitter. Check battery connections. |
| Motor does not spin or stutters. | Loose motor connections, incorrect motor wiring, or motor damage. | Check all three motor wire connections. Ensure they are firmly seated. If motor direction is wrong, swap any two motor wires. Inspect motor for damage. |
| ESC overheats and shuts down. | Excessive load, insufficient cooling, or incorrect gearing. | Reduce load on the vehicle. Ensure cooling fan is clear and functioning. Check motor and ESC temperatures. Adjust gearing if necessary. |
| No power to the receiver/servos. | BEC failure or loose receiver connection. | Check the ESC's receiver wire connection to the receiver. Ensure the ESC is powered on. If the issue persists, the BEC may be faulty. |
If you are unable to resolve an issue using the troubleshooting guide, please contact ARRMA customer support for further assistance.
8. Technical Specifications
Detailed specifications for the ARRMA BLX120 Brushless 4S ESC:
| Specification | Value |
|---|---|
| Battery Usage | 3S LiPo (11.1V) or 4S LiPo (14.8V) |
| Low Voltage Cut-Off (LVC) | 3.4V per cell |
| Thermal Protection Temperature | 125°C / 257°F |
| Over-Voltage Protection | Over 17.2V |
| BEC Voltage | 6V |
| BEC Current | 3A |
| ESC Length | 43mm / 1.69" |
| ESC Height | 34mm / 1.34" |
| ESC Width (Including hold-down tabs) | 54.5mm / 2.15" |
| ESC Weight | 150g / 5.3 oz |
| Receiver Wire Length | 170mm / 6.70" |
| Battery Wire Length | 225mm / 8.86" |
| Motor Wire Length (Including Connector) | 200mm / 7.87" |
| Switch Length | 21mm / 0.83" |
| Switch Width | 13.3mm / 0.52" |
| Switch Height | 16mm / 0.63" |
| Motor Bullet Connector Size | 4mm / 0.16" |
| Wire Specifications | 12AWG |
| ESC Battery Connector Type | 2xEC5 |
| Product Dimensions | 5.5 x 3.5 x 2 inches |
| Item Weight | 3.84 ounces |
9. Warranty and Support
For warranty information and technical support regarding your ARRMA BLX120 Brushless 4S ESC, please refer to the official ARRMA website or contact their customer service directly. It is important to retain your proof of purchase for any warranty claims.
You can find more information and contact details by visiting the official ARRMA store: ARRMA Store on Amazon.