ROCKSOLAR Keeper Series MPPT 20A-40A Solar Charge Controller

1. Overview

Thank you for selecting the ROCKSOLAR MPPT series solar charge controller. It features the most advanced MPPT control algorithm and the maximum power point tracking of the PV array, enabling it to capture maximum energy from the solar panel in any environment and significantly improve solar system utilization. The unit offers a dual display function (LCD and optional Remote header) and a standard communication interface for user extension applications and diverse monitoring needs. It is suitable for applications such as communication base stations, home power supply systems, traffic lights, solar street lamps, and courtyard lamp systems.

Key Features:

• Advanced MPPT maximum power point tracking technology with tracking efficiency no less than 99.5%.
• High-quality components ensure superior system performance and a maximum conversion efficiency of up to 97%.
• Super-fast maximum power tracking speed while maintaining tracking efficiency.
• Accurate identification and tracking of the maximum power point of multi-wave peaks.
• Reliable maximum input power of PV array for equipment safety.
• Wide PV array maximum power point operating voltage range.
• 12/24V automatic voltage identification.
• LCD dynamically displays operation data and working status.
• Various load control modes: General, Light Control, Dual Time, Pure Charger, and Timing modes.
• Supports Seal, GEL, Flooded, LifePO4, and Li (NiCoMn) O2 charging processes.
• Battery temperature compensation function.
• Power statistics recording function.
• Optional customization includes PC monitor and external display unit for real-time data view and parameter setting.
• RS485 communication method for maximizing communication needs in different scenarios.

3. Wiring

The diagram illustrates the connection of the MPPT solar charge controller.

[Diagram Description: The diagram shows the ROCKSOLAR MPPT charge controller. Connections are made from a PV Array (labeled 3) through a Breaker and Fuse to the controller's PV input. The controller's Load output is connected to a Load through a Fuse. The controller's Battery terminals are connected to a Battery (labeled 1) through a Fuse. An Inverter is connected to the Battery terminals, with an AC output. The diagram indicates the order of connection: 1. Battery, 2. Load, 3. PV Array, 4. Controller powered on.]

Order of Connection:

1. Connect battery.
2. Connect Load.
3. Connect PV array.
4. Controller is powered on.

After connecting the battery, observe the control system voltage and check if the display screen is lit. If it does not work or the display is abnormal, refer to section 6 for troubleshooting.

[Warning] NOTICE: This series of MPPT is a common positive controller. The positive poles of the PV array, battery, and load can be grounded simultaneously.

[Warning] NOTICE: If an inverter or other starting current device is used, please connect the inverter directly to the battery. Do not connect it to the controller's load terminal.

4. Description

4.1 Buttons

4.2 LCD Display Indicators

The LCD displays various parameters and status information. The following are the indicators:

• 1. PV array parameter indicator: Displays PV array data, such as voltage.
• 2. Battery parameter indicator: Displays battery data, such as voltage and temperature.
• 3. Load parameter indicator: Displays load parameter when active.
• 4. System voltage: The controller automatically adjusts technical data based on the system voltage shown on the LCD.
• 5. Numerical display area: Shows numerical values for parameters.
• 6. Timer setting function: Indicates timer settings.
• 7. Switch graphic symbol: Indicates switch status.
• 8. Unit symbol value: Displays unit symbols.
• 9. Warning indicator: Lights up when there is a fault.
• 10. Load status indicator: Shows Load ON or Load OFF.
• 11. Output power indicator: Lights up when the load terminal has output.
• 12. Battery capacity indicator: Shows battery capacity using a strip-type display.
• 13. Charge status indicator: Lights up when charging, flashes for float charge, and is off when not charging.

Default Night Display: The graphic symbol is lit when the solar panel input voltage is detected to be less than the sensor identification point voltage.

Default Daytime Display: The graphic symbol is lit when the solar panel input voltage is detected to be more than the sensor identification point voltage.

5. Installation Important Note

1. Install the controller in a well-ventilated area, away from direct sunlight and high temperatures. Do not install where water can enter the controller.
2. Use correct screws (M4 or M5, with cap diameter less than 10mm) to fix the controller to the wall or platform.
3. Ensure sufficient space between the wall and controller for cooling and cable connections.
4. Connect components to the charge controller in the specified sequence, paying close attention to positive and negative terminals. Do not insert fuses or turn on breakers during installation. The reverse order should be followed when disconnecting the system.
5. Always connect the battery first to allow the controller to recognize the system voltage.
6. The battery fuse should be installed as close to the battery as possible, ideally within 150mm of the battery group.
7. For positive grounding controllers, any positive connection of the solar load or battery can be earth grounded as required.
8. Ensure all terminals are tight after leaving the factory; loosen them first for proper connection.
9. Do not alter the connection sequence, as it may cause system voltage recognition faults.
10. Keep the cable length between the battery and controller as short as possible, ideally 30cm to 100cm.
11. [Warning] If a short circuit occurs on the controller terminals, it may result in fire or explosion. Exercise caution. It is strongly recommended to install a fuse at the battery side rated at 1.5 times the controller's rated current.
12. [Warning] If the battery is connected in reverse polarity, the controller's output will also have reverse polarity. Do not connect any load to the controller in this state, as it may destroy the load and the controller.
13. [Warning] The voltage of the solar panel can be very high under sunshine, potentially causing injury or damaging the controller. Ensure the PVmax is within the required safety MPP range.
14. To avoid injury from load voltage, first turn off the load output using the button, then connect the load to the controller. The controller does not offer reverse connection protection for the load. Take care, as reverse connection of the load can destroy the bulb.

6. Operation Steps

Main Interface

Upon electrification, the controller displays an initialization interface for 1 second before entering the main interface.

[Diagram Description: Shows the initial display with PV, BAT, LOAD icons and voltage, followed by a 1-second delay, then the main interface showing BAT voltage (e.g., 12.6V) and system voltage (12V).]

If there is no operation at the main interface for 20 seconds, the interface will automatically cycle through battery voltage, solar panel voltage, and environment temperature, with each display lasting 3 seconds. Long pressing the "SET" button for more than 5 seconds at the main interface will speed up this auto-exchange. Releasing the button will stop the speed-up.

[Diagram Description: Shows auto-exchange between BAT voltage (12.6V), PV voltage (12.7V), and temperature (26°C), all at 12V system voltage.]

Using Buttons

SET Button: Pressing the "SET" button under the main interface can turn the load on or off.

[Diagram Description: Shows the main interface with BAT voltage, and then pressing SET to toggle the load ON/OFF, displaying the load icon.]

MENU Button: Pressing the "MENU" button can navigate to the next menu from the main interface.

[Diagram Description: Shows navigation from Main Interface to Total Charge Power, then to Load status, Load disconnect voltage, Load reconnect voltage, Float voltage, Load mode, and System voltage select, all via the MENU button.]

Parameter Setup

a) Float Voltage Set Up

This parameter is the High Voltage Disconnection (HVD) voltage. The boost state voltage will increase by 0.6V based on HVD. The controller will start PWM function at this point (HVD), limiting voltage rising.

Press the "MENU" button to enter the float voltage menu. Long press the "MENU" button for more than 5 seconds; the parameter on the interface will flash, indicating setup state. Release the button. Press "MENU" again to increase data, press "SET" to decrease data. After setting the required value, long press "MENU" for more than 5 seconds to save and exit setup state. If no operation occurs for 20 seconds, it will automatically return to the main interface.

[Diagram Description: Shows the sequence of setting Float Voltage. Starts at 13.9V, then MENU+SET to 12.6V, then 20s later to 13.9V, then Long Press MENU 5s to 13.8V, then Long Press MENU 5s to 13.8V (Float Voltage).]

b) Low Voltage Reconnect Voltage (LVR)

When the battery voltage is low, the controller stops supplying power to the load. For the output to be reconnected, the battery voltage must be higher than the LVD voltage, or the "SET" button must be pressed to force release. The procedure is the same as for Float Voltage setup (a).

[Diagram Description: Shows the main interface with BAT voltage 12.6V.]

c) Low Voltage Disconnect Voltage (LVD)

When the battery voltage is low, the load output will be cut off. When the controller detects the battery voltage is less than the LVD point, the cut-off function activates immediately, and the controller status locks. Users must charge the battery. When the battery voltage is higher than the LVD voltage or the "SET" button is pressed to force release, the load output will resume. The procedure is the same as for Float Voltage setup (a).

[Diagram Description: Shows the LOAD output at 11.0V, then OFF.]

[Note] The default data for parameters a, b, and c have been carefully considered by the designer for actual use. Generally, users do not need to adjust them. Please refer to the battery supplier's suggestions to avoid damaging the battery.

d) Load Working Mode Selection

The controller defaults to a 24-hour load working mode. If the load working time is set to 24 hours, the load will operate continuously without fault. If set to less than 23 hours, it activates a load start timer or sensor function. If the battery capacity is sufficient, the load will start at sunset and operate for the set duration or until sunrise.

[Diagram Description: Shows the "Load mode" display with "24 H" and "ON" indicators.]

[Note] When the load operates in timer or sensor mode, if the reset working time is longer than the actual night time, the load output will close at sunrise, even if the set working time is not reached. For example, if the local night time is 10 hours and the user sets the working time to 12 hours, the output will close automatically after 10 hours, and the remaining hours will reset to zero. The load will then operate with the next sunset signal.

e) System Voltage Select

This section describes how to select the system voltage based on the battery type.

[Diagram Description: Shows the sequence for selecting system voltage. Starts from Battery type interface, then to Lead acid: 12/24V Auto (code -0600), then Lead acid: 12V (code -0601), then Lead acid: 24V (code -0602). Also shows LifePO4: 25.6V (code -0612) and LifePO4: 12.8V (code -0611), with arrows indicating navigation via MENU.]

7. Common Fault

8. Technical Specifications