Seplos Smart BMS 200A User Manual

1. Introduction

This manual provides detailed instructions for the installation, operation, maintenance, and troubleshooting of the Seplos Smart Battery Management System (BMS) 2.0 10E. This full-featured BMS is designed to monitor LiFePO4 and Li-ion battery packs from 7S to 16S configurations, supporting 24V to 48V nominal voltages and up to 200A current rates. It offers comprehensive protection features, accurate capacity calculation, and versatile communication options for seamless integration with various inverter systems.

2. Safety Precautions

• The BMS cannot be connected in series.
• The components of the BMS are designed to withstand a maximum voltage of 100V.
• Do not connect the external switch with other devices without permission. SEPLOS will not be responsible for any damage caused by unauthorized connections.
• Avoid any contact with the surface of battery cells during installation to prevent damage to the cell.
• Avoid any contact with the components of the PCB to prevent damage to the PCB.
• Operate the device in a dry and dust-free environment.
• After installation, check if the BMS is correctly connected if there is no voltage input and output.
• Always follow the guidance and use conditions specified in the data sheet.

3. Product Overview

The Seplos Smart BMS 2.0 10E is a sophisticated battery management system designed for optimal performance and safety of lithium battery packs. Below are the key components and their functions:

Image: Top view of the Seplos Smart BMS board.

3.1 Key Components

• Data Collecting Cable Connector: Used for connecting the data collecting cable to monitor individual cell voltages.
• Diode/Resistors: Essential for negative cell balancing, ensuring uniform charge across all cells.
• Transformer: Provides the necessary DC power supply to the internal chips of the BMS.
• Communication Section: Supports CAN/RS485/RS232 customization for communication with inverters and other devices. Goodwe/Growatt protocols are pre-programmed, with others customizable.
• Storage and Clock Section: Facilitates data recording and timekeeping. Data can be saved and accessed via the APP.
• Shunt Resistor: A 300A 75mV shunt resistor with 0.5% measurement accuracy for precise current monitoring.
• MCU (Main Control Unit): The central processing unit managing all BMS functions.
• AFE (Analog Front End IC): Responsible for collecting cell voltage and temperature data.
• Switch Connector: For connecting an external switch to control the BMS.
• LCD Screen Connector: Connects to an optional LCD screen for real-time battery status monitoring.
• Current Limiting Circuit: Limits the charging/discharging current to 10A to prevent overload.
• Heating Function (Optional): Heats the battery cells during low temperatures to maintain optimal performance.
• Charging/Discharging MOSFET: Control switches for managing battery charging and discharging processes.
• MOSFET Drive: Controls the connection and disconnection of the MOSFETs.
• CAN BUS: Communication interface for battery and inverters, with a baud rate of 500kbps.
• RS485 Interface: Communication interface for parallel battery packs and software, with a baud rate of 19200bps.
• LED Indicators: Includes 4 capacity lights, 1 running light, and 1 alarm light to indicate battery status.
• DIP Switches: Used for setting up the battery pack address, especially in parallel configurations.
• RESET Button: Used to power on/off the BMS.
• Pre-charge Circuit: Prevents the BMS from short circuits during initial connection.
• Inductance: Used for current limiting.
• Capacitors: Store and release electrical energy.
• Battery for Clock: Provides power supply to the internal clock.
• Aluminum Sheet: Dissipates heat generated by the BMS components.

4. Setup

4.1 Wiring Introduction

Proper wiring is crucial for the safe and effective operation of the BMS. Refer to the detailed wiring diagrams and pin definitions below.

Image: Communication methods for Seplos Smart BMS.

4.1.1 Wire Harness A (Black Connector)

4.1.2 Wire Harness B (White Connector)

4.2 Wiring Diagram

The following diagrams illustrate the typical wiring connections for the Seplos Smart BMS in various system configurations.

Image: Wiring diagram for parallel connection.

Image: System connection diagram with various Seplos products.

4.3 DIP Switch Setup

If multiple battery packs are connected in parallel, the DIP switches are used to assign a unique address to each pack. This allows the BMS to differentiate and manage each pack individually.

• Bits 1 to 4 are used for setting the address of individual paralleled packs.
• Bits 5 to 8 are used for setting the quantity of slave packs.

4.4 Parallel Communication

The BMS supports parallel communication via RS485. When battery packs are connected in parallel, the BMS requires address setup using DIP switches. If the DIP address is correctly set, powering on/off the master pack will power on/off all connected slave packs simultaneously. Note that if each pack has a different voltage or there is current output between paralleled packs, slave packs cannot be powered off together.

5. Operating

5.1 Working Modes

• Charging Mode: Activated when a charger is detected, and the charger voltage exceeds the battery voltage by 0.5V+. The charging MOSFET turns on, and when the charging current reaches the effective value, the BMS enters charging mode with both charging and discharging MOSFETs active.
• Discharging Mode: Activated when a load is detected, and the discharging current reaches the effective value.
• Standby Mode: The BMS enters standby mode when it is not in charging or discharging mode.
• Power Off Mode: The BMS enters power off mode if the battery is in standby for 48 hours and in under-voltage protection status, or if the reset/external switches are pressed.

5.2 LED Indicators

The BMS features 6 LED indicators:

• 4 White LEDs: Indicate State of Charge (SOC) status.
• 1 Red LED: Indicates warning, protection, or fault.
• 1 White LED: Indicates battery standby, charging, or discharging status.

Refer to the manual (Section 5.3.3) for detailed blinking explanations.

5.3 Power On/Off

• Power On/Start: Pressing the reset button in sleeping mode activates the BMS. LED indicators will light up sequentially, and the BMS enters running status.
• Power Off/Sleep: Hold the reset button for 3 seconds in standby or discharging mode. The LED indicators will blink sequentially, and the BMS enters sleep mode.

5.4 Bluetooth APP

The Bluetooth APP allows monitoring and configuration of BMS functions, parameters, and warning information. It provides access to battery information, communication status with the inverter, warning status, paralleling information, and is available in English.

5.5 BatteryMonitor Software

The BatteryMonitor software (available in Chinese and English) allows for monitoring parameter settings and data through a computer via the RS485 interface. Download the software and corresponding drivers from the official link: https://drive.google.com/drive/folders/10pxgNLHovcDZRVGrCZsSkfecBrRw-AdW?usp=sharing. Ensure to install the drive before installing the BatteryMonitor software.

6. Maintenance

6.1 Cell Balance

The BMS performs individual cell balancing in standby and charging modes through a power consumption circuit. Balancing activates when any individual cell voltage exceeds the equalization start voltage and the voltage difference exceeds a configurable threshold. Balancing stops when connected to a charger or when the voltage difference falls below the set threshold.

6.2 Firmware Updating

Firmware updates for the BMS can be performed via the RS485 interface.

6.3 Storage

The BMS includes a data storage module that records protection and warning statuses, recovery times, individual cell voltages, total pack voltage, charging/discharging capacity, current, and temperature. This data can be accessed and saved as Excel files via the BatteryMonitor software, with up to 300 historical data points stored.

7. Troubleshooting

7.1 Protection and Recovery

• Over-charging Protection: BMS enters this status if individual cell voltage exceeds the threshold. Recovery occurs when cell voltage decreases to the recovery threshold and SOC is below 96%, or when connected to loads.
• Over-discharging Protection: BMS enters this status if individual cell voltage drops below the threshold. The BMS will power off after 1 minute of communication with the inverter. Recovery is by pressing the reset button or charging, and checking if voltage reaches the recovery threshold.
• Charging Over-current Protection: Activated if charging current exceeds the threshold for a set delay. Recovery is automatic after a certain time or by discharging.
• Discharging Over-current Protection: Activated if discharging current exceeds the threshold for a set delay. Recovery is automatic after a certain time.
• Temperature Protection: High/low temperature warnings and protections for cells, ambient temperature, and MOSFETs. Recovery occurs when temperatures return to safe operating ranges.
• Short Circuit Protection: The BMS features a short-circuit detection and protection function. Recovery is automatic after 60 seconds if the short circuit is removed.

7.2 Compensation

Long copper bus bars or wires can cause significant voltage differences. If this occurs, check the connectors between cells. Voltage compensation can be set via the BatteryMonitor software by calculating resistance based on voltage difference and current. The default resistance compensation is between the anode of the 9th battery and the cathode of the 13th battery.

8. Specifications

8.1 Electrical Features

8.2 Dimensions

BMS size: 300mm x 100mm x 20mm (Length x Width x Height).

Image: LCD screen and adapter board.

The 50A BMS version does not include a heat dissipation sheet.

9. User Tips

• Inverter Compatibility: The Seplos BMS has been tested with many inverter brands. If your inverter brand is not explicitly listed, contact your inverter supplier for the protocol definition and share it with Seplos for confirmation.
• Software Connection: When using the BatteryMonitor software to view battery pack parameters, ensure you use an RJ45 to USB Adapter. It is recommended to purchase this adapter from Seplos to ensure proper functionality, as third-party adapters may have different hardware definitions.
• Parallel Operation: The BMS supports up to 16 units in parallel. Ensure correct DIP switch settings for addressing each pack.
• Offline Operation: The BMS can operate offline without a direct battery connection, which can be useful for initial setup and testing.

10. Warranty and Support

For warranty claims, technical support, or further inquiries, please contact JBD (Seplos) Official Store directly. Refer to the official user manual (PDF) for comprehensive support information.

You can find the full user manual in PDF format here: Seplos Smart BMS User Manual (PDF).