1. Introducción
This user manual provides detailed instructions for the Youmile MPPT 5A Solar Charge Controller, Model GR-YM-133. This module is designed for efficient solar power management, featuring Maximum Power Point Tracking (MPPT) to optimize charging of various battery types from solar panels. It is suitable for a wide range of applications including solar street lights, wind turbines, and general battery charging systems.

Figure 1: Youmile MPPT 5A Solar Charge Controller module and included 24 AWG power cable.
2. Características principales
- Funcionalidad MPPT: Advanced Maximum Power Point Tracking for optimal solar energy utilization.
- Volumen de entrada ampliotage Rango: Supports DC 8-28V input (DC only).
- Volumen de salida ajustabletage: Continuously adjustable DC 5-26V output.
- Alta corriente de salida: Corriente de carga máxima de 5A.
- Carga inteligente: Three-phase automatic intelligent charging mode with automatic current adjustment.
- Indicador de estado de carga: Visual indication for fast charge (red) and full charge (red/blue alternating).
- Alta eficiencia: Conversion efficiency up to 95%.
- Características de protección: Includes input and output reverse connection protection.
- Low Quiescent Current: Only 3mA no-load current.
- Industrial Grade Temperature: Funciona de forma fiable desde -40 °C hasta +85 °C.
3. Especificaciones técnicas
| Parámetro | Valor |
|---|---|
| Propiedades del módulo | MPPT maximum power point tracking, intelligent automatic charge management |
| Vol de entradatage | DC 8-28V (DC input only) |
| Vol de salidatage | CC 5-26 V (ajustable continuamente) |
| Corriente de salida | 5A max |
| Indicador de carga | Red (fast charge), Red/Blue alternating (full charge), Auto-stop |
| Función MPPT | Yes, adjustable MPPT voltage |
| Diferencia de presión mínima | 1V |
| Temperatura de funcionamiento | -40°C to +85°C (Industrial grade) |
| Regulación de carga | ±1% |
| Volumentage Regulation Rate | ±0.5% |
| Eficiencia de conversión | Max 93% / Peak 95% (varies with lighting conditions) |
| Método de carga | Three-phase intelligent automatic charging mode |
| Corriente sin carga | 3 mA |
| Protección de entrada inversa | Sí |
| Protección de salida inversa | Sí |
| Dimensiones (aprox.) | 12.3 x 7.9 x 2.7 cm (Dimensiones del paquete) |
| Peso (aprox.) | 40 gramos (Peso del paquete) |
4. Contenido del paquete
- 1 x Youmile MPPT 5A Solar Charge Board
- 1 x 30cm 24AWG Power Cable
5. Configuración y conexión
Before connecting the module, ensure all power sources are disconnected. Observe polarity carefully to prevent damage, although the module includes reverse connection protection.
5.1. Identifying Terminals

Figure 2: Input and Output Terminals. The blue terminal block has clearly labeled connections.
- VIN+ / GND: Input terminals for the solar panel (DC 8-28V). Connect the positive (+) lead of the solar panel to VIN+ and the negative (-) lead to GND.
- BAT+ / BAT-: Output terminals for the battery. Connect the positive (+) lead of the battery to BAT+ and the negative (-) lead to BAT-.
5.2. Procedimiento de conexión
- Conecte la batería: First, connect your battery (e.g., 6V, 12V, 8.4V, 12.6V, 16.8V lithium, etc.) to the BAT+ and BAT- terminals. Ensure correct polarity.
- Conectar el panel solar: Next, connect your solar panel (1W-100W, 9V-28V) to the VIN+ and GND terminals. Ensure correct polarity.
- Initial Adjustment (Important):
- Vol de salidatage Ajuste: Before connecting the battery, you can adjust the output voltage using the potentiometer labeled V-ADJ (often blue, multi-turn). Turn the potentiometer clockwise to increase voltage, counter-clockwise to decrease. Adjust to the desired charging voltage for your battery type (e.g., 14.4V for a 12V lead-acid battery, 4.2V per cell for lithium-ion).
- Volumen MPPTtage Ajuste: The potentiometer labeled U-MPPT (often blue, multi-turn) adjusts the Maximum Power Point Tracking voltage. With the solar panel connected and under maximum illumination, adjust this potentiometer to achieve the manufacturer's specified MPPT voltage for your solar panel. This optimizes power transfer from the panel to the battery.
- Observe Indicator: The charge indicator LED will illuminate. A red light indicates fast charging. When the battery is fully charged, the LED will alternate between red and blue, and charging will automatically stop.

Figura 3: Arriba view of the module, highlighting the V-ADJ and U-MPPT potentiometers for adjustment.
6. Instrucciones de funcionamiento
Once properly connected and adjusted, the Youmile MPPT 5A Solar Charge Controller operates automatically. It continuously tracks the maximum power point of the solar panel to ensure efficient charging.
6.1. Proceso de carga
- The module employs a three-phase intelligent automatic charging mode (constant current, constant voltage, float charge).
- The solar energy tracking feature dynamically adjusts the charging current based on available solar power and battery state.
- The charge indicator LED provides real-time status:
- Rojo sólido: Fast charging in progress.
- Alternating Red/Blue: Battery is fully charged. Charging will automatically terminate.
6.2. Compatibilidad
This controller is versatile and can charge various battery types, including:
- Baterías de plomo-ácido de 6 V y 12 V
- Nickel-Cadmium (NiCd) Batteries
- Nickel-Metal Hydride (NiMH) Batteries
- Lithium-Ion (Li-ion) Battery Packs (e.g., 8.4V, 12.6V, 16.8V)
- Lithium Iron Phosphate (LiFePO4) Batteries (2-4 strings)
7. Mantenimiento
The Youmile MPPT 5A Solar Charge Controller is designed for low maintenance. Follow these guidelines to ensure optimal performance and longevity:
- Manténlo limpio: Periodically inspect the module for dust or debris accumulation. Gently clean with a soft, dry cloth. Do not use liquids or abrasive cleaners.
- Ventilación: Ensure the module is installed in a location with adequate airflow to allow the heatsink to dissipate heat effectively. Avoid enclosing it in unventilated spaces.
- Conexiones: Periodically check all wire connections to ensure they are secure and free from corrosion. Loose connections can lead to inefficient operation or damage.
- Condiciones ambientales: While designed for industrial temperatures, avoid exposing the module to extreme moisture or direct water contact.

Figura 4: Lado view of the module, showing the integrated heatsink for thermal management.
8. Solución de problemas
If you encounter issues with your MPPT charge controller, refer to the following common problems and solutions:
| Problema | Posible causa | Solución |
|---|---|---|
| No charge indicator light / No output |
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| La batería no se carga completamente |
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| Sobrecalentamiento del módulo |
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Si los problemas persisten después de seguir estos pasos, comuníquese con atención al cliente.
9. Información de garantía
This product is sold by YoumileDirect and fulfilled by Amazon. For information regarding returns and replacements, please refer to Amazon's standard return policy, which typically allows for returns within 30 days of receipt for most products. Please retain your proof of purchase for any warranty claims or return requests.
For specific warranty details beyond the Amazon return policy, please contact YoumileDirect directly through the Amazon platform.
10. Atención al cliente
For technical assistance, troubleshooting not covered in this manual, or general inquiries, please contact Youmile customer support.
- Soporte en línea: Visit the Youmile store page on Amazon.com.be or the seller's profile (YoumileDirect) to find contact options.
- Descarga del Manual de Usuario: A digital version of this manual may be available for download.
When contacting support, please provide your product model number (GR-YM-133) and a detailed description of the issue.





