SEPLOS SMART 16S 100A BMS USER MANUAL

2.1 Cell and pack voltage detection

By detecting cell voltage in real-time, the BMS provides over/under voltage warnings and protections. At temperatures between 0°C and 45°C, the measured voltage difference is approximately ±10mV. Between -20°C and 0°C, and 45°C and 70°C, the measured voltage difference is ±30mV. Warning and protection threshold values are configurable through software.

2.2 Cell/ambient/MOSFET temperature detection

By detecting the temperature of cells (4 of the 16 cells), ambient temperature, and the PCB board temperature in real-time via NTC sensors, the BMS provides high/low temperature warnings and protections. The measured difference is ±2°C. Cell temperature sensor NTC value is 10kΩ, with a B-value of 3435. Warning and protection threshold values are configurable through software.

2.3 Charging/discharging current detection

Using current sense resistors in the charging/discharging circuit, the BMS detects and monitors input and output current in real-time, providing over current warnings and protections. When the temperature rise is less than 40°C, the measured accuracy is up to ±1%. Warning and protection current thresholds are configurable through software.

2.4 Short circuit protection

The BMS features short-circuit detection and protection functions.

2.5 Pack capacity and cycle life calculation

The BMS calculates the remaining capacity in real-time. It determines the capacity for the first time when the battery pack completes a full charging and discharging cycle, with an SOC calculating accuracy of ±5%. The BMS counts the number of charging/discharging cycles as an indicator of aging. When the accumulated discharge capacity reaches 80% of the design capacity, the cycle count increases. Capacity parameters are configurable through software.

2.6 Charging/discharging MOSFET

Low impedance, high current MOSFETs are optimized for power-on, zero handoff, and withstanding charging voltage for large capacitive loads and backup power supply. In charging or standby status, cells can be equalized, which greatly increases battery life span and cycle life. Voltage and voltage difference thresholds are configurable through software.

2.7 LED indicator

There are 6 LED indicators: 4 white LEDs for SOC status, 1 red LED for warning, protection, and fault indication, and 1 white LED for battery standby, charging, and discharging status.

2.8 Standby mode

The BMS features an auto-sleeping function.

• Automatically standby: If the battery has not charged or discharged for 48 hours, the BMS enters standby mode automatically. If the battery is in discharge protection status and maintains communication for 1 minute, the BMS will sleep automatically.
• Manually standby: Hold the 'reset' button for 6 seconds; the indicators will light up in order, and the BMS enters sleeping mode. Disconnecting the external switch also puts the battery pack into standby mode.

Sleeping mode function is configurable through software.

2.9 Power on/off with master pack

Paralleled battery packs can be powered on with one-click. When battery packs are connected in parallel, the BMS requires address setup via DIP switch. If the DIP address is correctly set, powering the master pack on or off will also power all slave packs on or off together. (Note: If packs have different voltages and current flows between them, slave packs cannot be powered off.)

2.10 CAN/RM485/RS485 interface

CAN BUS enables communication between the battery and inverter. CAN communication protocols vary depending on the inverter. The Seplos Default CAN protocol is compatible with Pylontech, Goodwe, DEYE, and TBB. Protocols can be switched via software to optional ones like Growatt, Victron, SMA, Sofar, Solis, and Studer.

RS485 communication enables communication between the battery and inverter. RS485 can recognize Pylontech, Growatt, and SRNE protocols. RS485 communication facilitates data monitoring, operation control, and parameter setting through computers or other devices via telemetering, telesignalization, remote regulating, and remote control commands.

2.11 Parallel communication

Connect battery packs through RS485 and set addresses using 8 DIP switches. To check paralleled packs information:

• Connect the paralleled packs via RS485 interface and then connect to a master computer.
• Connect the paralleled packs via RS485 interface, then connect the master pack to the inverter via CAN/RM485 interface.

2.12 Battery information storage

Each time the battery system status changes, the BMS saves data including warnings, protection triggers, and releasing data. The BMS can also save data for a specific period by setting start time, end time, and time interval. Up to 300 historical data points can be recorded and stored, and all data can be read and saved as an Excel file via a master computer.

2.13 Battery parameter configuration

Parameters such as individual cell voltage, total voltage, charging and discharging over current, cell and ambient high/low temperature, cell balancing and equalization, number of cells in series, battery capacity, and other battery management parameters are all configurable through software.

2.14 Battery function configuration

Manage voltage, temperature, and current related monitoring and controlling functions, as well as capacity calculation functions, through software.

2.15 Precharge

The pre-charge function activates when the BMS or discharge MOSFET powers on. The pre-charge time ranges from 1mS to 5000mS. This function effectively protects the BMS from short circuits and is specifically designed for applications with capacitive loads.

2.16 Dry contact

The BMS features two circuits of dry contact output for:

• SOC warning and protection, low voltage warning and protection, temperature abnormal warning and protection, over charging/discharging warning and protection, over voltage warning and protection.
• Temperature sensor failure warning, cell voltage difference failure, transient over current protection, short circuit protection, and cell over voltage protection + 30mV.

2.17 Aerosol supportable

The BMS supports transmitting abnormal information via aerosol dry contact and notifying the customer of the abnormal status.

2.18 Bluetooth

Functions, parameters, and warning information can be monitored and configured through a Bluetooth APP. This includes battery information, BMS-inverter communication, warning status, parameters, function switch configuration, and paralleling information. An English version is available.

2.19 Compensation

Long copper bus bars or wires can cause significant voltage differences. If the voltage difference is too large, check the connectors between the cells. Voltage differences caused by long bus bars and wires can be compensated for using the upper computer system. Check the voltage difference between bus bars or wires during discharging and calculate resistance compensation using the formula: resistance = voltage difference / current. Set the resistance value in the upper computer system. The default resistance compensation is between the anode of the 9th battery and the cathode of the 13th battery. Two additional resistance compensation settings are reserved for special occasions. Note: Please confirm with SEPLOS before setting the resistance compensation value to ensure cell consistency.

2.20 Charging current limiting

Two types of current limitation are available to meet different needs: active current limitation and passive current limitation.

• Active current limitation: When charging, the current limitation MOSFET remains connected, limiting the charging current to 10A.
• Passive current limitation: When charging, the charging MOSFET remains connected. Once the charging current exceeds the over current warning threshold (default 100A), the charging current limitation activates, reducing the current to 10A. The BMS detects the charging current every 5 minutes to check if passive current limitation should be activated. The default passive current limitation threshold is editable.

A diagram illustrates the charging activation process: Power on/Charge activate → Direct charge mode → (No) → Passive current limit Start-up current → (Yes) → Current limit to 10A Charge. It also shows an option to recheck charge current after 5 minutes.

2.21 Automatically identification

If the automatic identification function is enabled, each paralleled battery pack is assigned an identification based on wiring connections, eliminating the need for DIP switches.

2.22 BatteryMonitor software

The software is named BatteryMonitor and is available in Chinese and English versions. Refer to the installation guide for installation. Download the software from: https://drive.google.com/drive/folders/10pxgNLHovcDZRVGrCZsSkfecBrRw-AdW?usp=sharing

2.23 Firmware updating

Firmware can be upgraded via the RS485 interface.

3. Diagram

A block diagram illustrates the system components, including Discharge MOSFET, Charge MOSFET, Precharge Module, Current limiting module (Optional), Voltage Detecting, Cell balancer, AFE, Temperature, Current detecting resistance, MCU, Storage Module, Heating Module (Optional), Dry Contact (Optional), Communication Module, LCD/Bluetooth Module, LED Module, B+, B-, P+, P-.

4. Electrical features

5. Basic parameters