Introduction
This manual provides essential information for the safe and efficient operation of your CDIYTOOL 100A MPPT Solar Charge Controller. This controller is designed for 36V, 48V, and 60V battery systems and features an LCD display, multiple load control modes, and dual USB outputs. Please read this manual thoroughly before installation and use.
The controller automatically adapts to 36V/48V/60V systems and is not suitable for 12V/24V systems. It utilizes innovative MPPT technology for high tracking efficiency, detecting the maximum charging current.
Safety Instructions
Always adhere to the following safety guidelines to prevent injury and damage to the controller or other components.
- Ensure the battery has sufficient voltage for the controller to recognize the correct battery type upon first use.
- Connect the battery to the controller first, then connect the solar panels. Reversing this order can damage the controller.
- The maximum input voltage is 50V. Ensure your solar panel configuration does not exceed this limit. For example, a 19V photovoltaic panel matches a 12V battery, and a 38V photovoltaic panel matches a 24V battery. When a 38V panel is connected, the maximum voltage may reach 42V.
- The controller is suitable for various battery types (including open, lead-acid, gel, and lithium batteries). Refer to the controller's settings for specific battery types.
- The controller provides protection against overvoltage, short circuit, overload, overcharge, and over-discharge.
- Do not attempt to disassemble or repair the controller yourself. Contact qualified personnel for service.

Image: Excerpt from the user manual detailing safety instructions and a connection diagram.
Product Features
- Multi-function LCD Display: Provides real-time display of charging current, discharge current, and power generation.
- MPPT Technology: Innovative Maximum Power Point Tracking with high efficiency (up to 99%) for optimal solar energy harvesting.
- Reliable Protection: Includes overvoltage, short circuit, overload, overcharge, and over-discharge protection.
- Automatic Focusing MPPT Tracking: Ensures high charging efficiency and bidirectional focusing tracking.
- Temperature Compensation: Automatically adjusts charging voltage based on ambient temperature changes.
- Dual USB Outputs: Provides 5V/2A output for charging mobile devices.

Image: Front view of the CDIYTOOL 100A MPPT Solar Charge Controller, highlighting the LCD display and dual USB ports.
Setup and Installation
Follow these steps for proper installation of the solar charge controller:
- Prepare Wiring: Ensure all wires are correctly sized for the expected current and are properly insulated.
- Connect Battery: Connect the battery to the charge controller first. Ensure correct polarity (+ to + and - to -). The controller requires sufficient battery voltage to recognize the system type.
- Connect Solar Panel: Connect the solar panel(s) to the charge controller. Ensure correct polarity. Do not exceed the maximum input voltage of 50V.
- Connect Load (Optional): Connect your DC load to the load terminals of the controller. The controller can manage load output based on settings.

Image: Connection diagram illustrating how to connect solar panels, battery, and load to the charge controller.

Image: Detailed view of the controller with labels for its components, including buttons, LCD, USB ports, and connection points.
Operating Instructions
The controller features an LCD display and three buttons for operation: Menu, Page Up, and Page Down/Manual.
LCD Display
The LCD displays various parameters including battery voltage, charging current, discharge current, and system status. The icons on the display indicate solar panel activity, battery charge level, and load status.
Button Functions
- Menu Button: Press to enter the menu interface and cycle through different settings. Long press to modify parameters.
- Page Up Button: Used to increase values or navigate upwards in menus.
- Page Down/Manual Button: Used to decrease values or navigate downwards in menus. Also functions as a manual load control switch (on/off) when on the main interface.
USB Charging
The controller is equipped with dual USB ports providing 5V/2A output for charging compatible devices such as mobile phones and tablets.

Image: Demonstration of the controller's dual USB ports being used to charge a mobile phone.
Maintenance
Regular maintenance ensures the longevity and optimal performance of your solar charge controller.
- Inspect Connections: Periodically check all wiring connections for tightness and corrosion. Loose connections can lead to power loss or overheating.
- Clean Controller: Keep the controller clean and free from dust and debris. Use a dry cloth to wipe the surface. Do not use liquid cleaners.
- Monitor Performance: Regularly check the LCD display for normal operation and expected voltage/current readings.
- Battery Health: Ensure your battery is well-maintained and within its recommended operating parameters.
Troubleshooting
This section provides solutions to common issues you might encounter.
| Situation | Probable Cause | Solution |
|---|---|---|
| No display on screen | Battery not connected or low voltage | Connect battery, check battery voltage |
| No charge when sunny | Solar panel reversed or open circuit | Reconnect solar panel, check wiring |
| Load not working | Load short circuit, overload, or over-discharge protection | Check load wiring, reduce load, or charge battery |
| Controller not charging | Solar panel voltage too low or battery full | Ensure sufficient solar input, check battery status |
The controller includes built-in protections for reverse polarity, overvoltage, short circuit, overload, overcharge, and over-discharge. If an issue persists after troubleshooting, contact customer support.
Specifications
| Parameter | Value |
|---|---|
| Model | 4yhujuyj |
| Brand | CDIYTOOL |
| Rated Current | 100A |
| System Voltage | 36V/48V/60V Auto Adapt (Not for 12V/24V) |
| Max Solar Input Voltage | 50V |
| USB Output | Dual 5V/2A |
| Display Type | LCD |
| Item Weight | 14.4 ounces |
| Package Dimensions | 6.81 x 3.98 x 2.01 inches |

Image: Diagram showing the physical dimensions of the solar charge controller.
Additional Resources and Support
For further assistance or to access the mobile application for monitoring, please refer to the following:
Mobile Application
The BL-912V APP can be installed on your Android phone to monitor and control the solar charge controller. Scan the QR code below or visit the provided link to download and install the application.
Download Link: http://fir.sdhzwl.cn/5w4b
The mobile phone app allows for remote monitoring of charging and discharging data, daily power generation, and other functions.

Image: Section of the user manual detailing the BL-912V APP installation process, including a QR code.
Warranty and Customer Service
For warranty information or technical support, please contact CDIYTOOL customer service through the platform where you purchased the product. Keep your purchase receipt for warranty claims.
Typical Applications
The CDIYTOOL MPPT Solar Charge Controller is suitable for a variety of off-grid solar power applications, including:
- Residential solar power systems
- RV and marine solar setups
- Solar street lighting
- Remote monitoring stations
- Agricultural irrigation systems

Image: Examples of typical applications for the solar charge controller in various settings.