XY12550S Digital DC Adjustable Step-Down Power Supply User Manual

1. Product Overview

The XY12550S is a high-performance digital DC adjustable step-down power supply module, designed for applications requiring constant voltage (CV), constant current (CC), and constant power (CW) output. It features MPPT solar charging capabilities, a 1.8-inch full-color LCD, and supports various communication methods for remote control and monitoring.

Key Features:

• Supports firmware upgrade, MPPT solar charging, and serial communication.
• 1.8-inch high-brightness full-color LCD screen with full viewing angle, customizable color scheme, and 4-way rotation.
• Features input reverse polarity protection and output reverse current protection for comprehensive safety.
• Gold-plated display board for better conductivity, oxidation resistance, and durability.
• Dual intelligent temperature-controlled PWM fans with variable speed and a large heat sink for low noise and efficient cooling.
• Common-mode inductor for the input, significantly reducing input ripple and achieving low output ripple.

2. Setup Instructions

2.1 Safety Precautions

• Do not connect AC power to the input, especially 220V mains power.
• The maximum input voltage should not exceed 145V; 140V is recommended. Do not reverse the polarity.
• This is a DC-DC converter; the maximum output voltage = input voltage * 0.945.
• Ensure the unit is OFF before connecting the battery. Avoid reverse polarity connection to prevent device damage or fire hazards.

2.2 Component Identification and Connections

Refer to the diagram below for identifying components and making connections.

Figure 2.1: Main Board Connections and Components

2.3 Basic Wiring

1. Connect your DC input power source to the IN+ and IN- terminals. Observe polarity.
2. Connect your load or battery to the OUT+ and OUT- terminals. Observe polarity.
3. For MPPT solar charging, connect the solar panel to the input and the battery to the output. Attach the external temperature probe to the battery.

Figure 2.2: MPPT Solar Charging Setup

2.4 Serial Communication Interface

The module supports standard Modbus protocol for serial communication. It features independent dual serial ports, including a serial TTL port and an on-board 485 communication port.

Figure 2.3: Serial Communication Interface

You can connect an XY-K485X module for 485 bus control or a WiFi module for APP and web-based networking control.

Figure 2.4: Modbus Communication Options

2.5 Bare Board Configuration (if applicable)

If using the bare board version, note that switches, potentiometers, and dial switches will be pre-welded. If a set with a screen meter is purchased, these are not welded by default.

The bare board supports independent MPPT and analog 0.3-10V control, with serial communication and on-board 485 communication (both can be used simultaneously). The output voltage is adjustable from 0-85V, and the output current is adjustable from 0-50A.

Analog control is only available in the numerical control screen mode. In potentiometer mode, the output voltage (constant voltage) can only be controlled through the potentiometer; the constant current value can be set via a dip switch, with a total of 16 gears to meet most scenarios.

Figure 2.5: Bare Board Configuration

3. Operating Instructions

3.1 Control Panel and Button Functions

The control panel features a 1.8-inch full-view high-brightness true color LCD and silicone buttons with indicator lights.

Figure 3.1: Control Panel Design

Figure 3.2: Universal Button Functions

• VSET Button: Short Press: Set voltage CV. Long Press: Quickly call up data set M1.
• SW Button: Short Press: Enter quick settings. Long Press: Enable four-way screen rotation.
• ISET Button: Short Press: Set current CC. Long Press: Enter or exit the data group settings UI.
• Encoder Button: Short Press: Shift. Long Press: Lock the button.
• Power Button (ON/OFF): Short Press: Turn power output on/off. Long Press: Shut down.

3.2 Setting Voltage and Current

There are three primary ways to set voltage and current:

Figure 3.3: Voltage and Current Setting Methods

1. Quick Setup Mode:
   1. Press the V-SET/I-SET button briefly to enter voltage/current setting mode.
   2. Use the SW button or encoder button to move between digits.
   3. Rotate the encoder to adjust the voltage/current value. Once set, press V-SET/I-SET briefly to save and exit.
2. Encoder Mode:
   1. Press the encoder button briefly to activate the parameter (voltage/current) you want to set.
   2. Press the encoder button to switch between full selection and digit selection. In full selection, all digits are highlighted. Rotate the encoder to switch between setting voltage or current. In digit selection, the selected digit is highlighted. Rotate the encoder to adjust the value.
   3. To finish, either hold the encoder button/SW button for 2 seconds or wait 6 seconds without any button press. All settings are saved automatically.
3. Remote Control Mode: Use an infrared remote control or 433M wireless remote control module to set voltage and current directly with the remote's numeric keypad.

3.3 Display Interfaces

The 1.8-inch LCD supports various display modes and customizable color schemes.

Figure 3.4: Multiple Display Interfaces

Figure 3.5: Customizable Display Colors

3.4 Screen Rotation

The display supports 360-degree rotation for optimal viewing from any angle.

Figure 3.6: 360° Screen Rotation

To enable four-way rotation: Long press the SW button on the main UI.

3.5 Advanced Functions

Figure 3.7: Advanced Control Functions

• Lock Function: Hold the encoder button for more than 2 seconds to lock the buttons and prevent accidental changes. Hold for more than 2 seconds again to unlock.
• Quickly Recall Data Sets: Hold the V-SET button to quickly load the M1 data set. To select a different data set, hold the I-SET button to open the data set selection window. Rotate the encoder to choose the desired data set, then briefly press the SW/encoder button to load it.
• Quickly Adjust System Parameters in the Status Bar: On the main screen, briefly press the SW button to select a status bar parameter. Rotate the encoder to switch between parameters. Briefly press the SW button or encoder button to adjust the parameter or open the parameter setting interface. Use the encoder to set the value. To save and exit, either hold the SW button/encoder button or wait 6 seconds without any button press. All settings are saved automatically.

3.6 MPPT Solar Charging

The module supports MPPT solar charging with automatic stop when fully charged and automatic charging at low battery, enabling intelligent battery charging management. It includes BCH automatic charging and BTF full-charge auto-stop functions for unattended operation.

Precaution: Turn on the output ONLY after the battery icon appears on the screen to initiate charging.

3.7 Constant Voltage (CV), Constant Current (CC), Constant Power (CW) Features

Figure 3.8: CV, CC, CW Features Introduction

• Constant Voltage (CV): When constant power is not turned on, the power supply functions as a constant voltage source. If the load current is less than the set constant current value, the output voltage is the set CV, and the current is adaptive.
• Constant Current (CC): When constant power is not turned on, the power supply functions as a constant current source. If the load current is greater than the set constant current value, the output current is the set CC, and the voltage is adaptive.
• Constant Power (CW): After the constant power function is turned on, the constant current value defaults to the maximum value. The constant voltage value CV serves as the initial voltage. The equivalent resistance R of the load is calculated using Ohm's law R=U/I. The constant power is calculated based on the set constant power value using the formula P=U/R.

Constant Power Switch and Constant Power Value Setting:

1. In the system parameter settings UI, select the CW option. Turn ON to enable constant power, and turn OFF to disable constant power.
2. After enabling constant power, press ISET briefly on the main interface to modify the value of constant power.

3.8 Network Control and Group Control

The module supports network control via PC host computer software (Sinilink) and mobile APP (Android/iOS), allowing remote control and monitoring with unlimited distance. It also supports email notifications and cloud records.

Figure 3.9: Network Control Overview

The digital control panel supports one-to-many group control via the 485 bus. This allows collective management of power supply activation/deactivation, voltage/current settings, achieving efficient one-to-many control.

Figure 3.10: Group Control Setup

Activating Group Control Function: On the main power supply interface, briefly press the SW button to select the status bar. Rotate the encoder to choose the group control switch activation icon, then briefly press the encoder button to open the selection dialog. Press the SW or encoder button to select and rotate the encoder to ON to enable group control mode. When setting voltage, current, or power on/off, the changes will automatically synchronize to all devices on the 485 bus (Note: Device addresses on the bus must be unique). Hold the SW button or wait 6 seconds without operation to exit and save settings automatically.

3.9 Remote Control Operation

The module supports control via infrared and 433M wireless remote control modules, providing convenience and speed.

Figure 3.11: Remote Control Compatibility

3.10 Operational Demonstration Video

Video 3.1: Demonstration of setting voltage/current, resetting capacity/energy/runtime, navigating data set parameters, and remote control operation.

4. Maintenance

4.1 General Care

• Keep the device clean and free from dust. Use a soft, dry cloth for cleaning.
• Ensure proper ventilation to prevent overheating. The dual intelligent temperature-controlled PWM fans are designed for efficient cooling.
• Avoid exposing the device to moisture or extreme temperatures.

4.2 Firmware Upgrades

The module supports firmware upgrades to experience new features. At present, it only supports firmware upgrade through the WiFi module. Future upgrades may include multi-serial port host computer software.

Figure 4.1: Firmware Upgrade Interface

Important: Do not power off during the product upgrade process. If the product upgrade fails, you can press and hold the power button to power on the product and force it into the upgrade mode.

5. Troubleshooting

5.1 Protection Mechanisms

The device is equipped with comprehensive protection features:

Figure 5.1: Protection Mechanisms

• LVP (Input Under-Voltage Protection): 10-145.0V (default 10V)
• OVP (Over-Voltage Protection): 0-130.0V (default 130.0V)
• OCP (Over-Current Protection): 0-52A (default 52A)
• OPP (Over-Power Protection): 0-6500W (default 6300W)
• OTP (Over-Temperature Protection): 60-110°C (default 110°C)
• OHP (Over-Time Out Protection): 1 minute - 99 hours 59 minutes (off by default)
• OAH (Over-Capacity Protection): 0-4200KAh (off by default)
• OWH (Over-Energy Protection): 0-4200KWh (off by default)
• ETP (External Over-Temperature Protection): 0-110°C (off by default)
• Reverse Polarity Protection: Yes
• Output Reverse Current Protection: Yes

5.2 Common Issues and Solutions

• Device not powering on: Check input voltage and polarity. Ensure connections are secure.
• Incorrect voltage/current readings: Verify calibration if possible, or check for loose connections.
• Output not enabling during MPPT charging: Ensure the battery icon appears on the screen before turning on the output.
• Firmware update failure: Do not power off. Press and hold the power button to force the device into upgrade mode and retry.

6. Specifications

Detailed technical specifications for the XY12550S module:

Figure 6.1: Product Parameters and Protection Mechanisms

Table 6.1: XY12550S Product Specifications

6.1 Dimensions

Figure 6.2: Product Dimensions

7. User Tips

• For MPPT solar charging, always ensure the battery icon appears on the screen before enabling the output to prevent damage.
• When performing firmware updates, ensure a stable power supply and do not interrupt the process. If an update fails, the device can be forced into upgrade mode by holding the power button during startup.
• If you purchase the bare board version, note that certain components like switches and potentiometers are pre-welded, unlike the full set with a screen meter.
• Utilize the remote control feature for convenient adjustments, especially when the unit is installed in a hard-to-reach location.
• Take advantage of the customizable display colors to personalize your user experience and improve readability.

8. Warranty and Support

For warranty information, technical support, or service inquiries, please contact your original seller or the manufacturer directly. Keep your purchase receipt as proof of purchase.