MPP Solar RS485 - User Manual

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BMS RS-485 Card/Box Quick Guide

V.1.3

Thank you for purchasing RS485 card/box. This manual contains instructions and warnings that

should be followed during the installation, operating and storage of the card. Please keep this

manual for further reference.

Applicable models:

 Hybrid inverter 3KW, 4KW, 5KW and 5.5KW

 3-phase hybrid inverter 10KW and 15KW

 Single phase off-grid inverter 4KW/5KW

 Split phase off-grid inverter 6KW

 Online 48V 3KVA/5KVA/6KVA UPS

Before installation, please make sure this RS-485 card/box is compatible to your

existing inverter.

1. Product Introduction

If the inverter is built in intelligent slot, it can work with RS485 card by simply inserting the

RS485 card. RS485 external box can provide communication slot for the inverter without

intelligent slot. No matter it’s RS485 card or RS485 box, it provides communication between

inverter and lithium battery.

Here are the detailed functions:

 Via the communication between the inverter and lithium battery, it’s able to re-configure

the charging voltage, charging current, battery discharge cut-off voltage and max.

discharge current, according to the lithium battery parameters.

 Have unit start or stop charging according to the status of lithium battery.

 Have unit start or stop discharging according to status of lithium battery.

Special Precautions

 If this card/box must be stored prior to installation; storage must be in a dry place

 The admissible storage temperature range is from -10ºC to +70ºC.

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The BMS RS-485 Card/Box is a communication interface designed to facilitate interaction between an inverter and a lithium battery. It comes in two forms: an RS-485 card for inverters with an intelligent slot, and an RS-485 external box for inverters without an intelligent slot. Both versions serve the crucial function of enabling communication between the inverter and the lithium battery, thereby optimizing the battery's performance and ensuring its safe operation.

Function Description:

The primary function of the BMS RS-485 Card/Box is to establish a communication link that allows the inverter to receive and act upon information from the lithium battery's Battery Management System (BMS). This communication enables several key functionalities:

Re-configuration of Charging Parameters: Based on the lithium battery's specific parameters, the device allows the inverter to dynamically adjust the charging voltage and charging current. This ensures the battery is charged optimally, prolonging its lifespan and preventing overcharging or undercharging.
Re-configuration of Discharging Parameters: Similarly, the device enables the inverter to re-configure the battery discharge cut-off voltage and maximum discharge current. This protects the battery from deep discharge, which can significantly reduce its capacity and lifespan.
Start/Stop Charging Control: The inverter can initiate or terminate the charging process based on the real-time status of the lithium battery. For instance, if the battery is fully charged or if there's an internal fault detected by the BMS, the inverter can stop charging.
Start/Stop Discharging Control: The inverter can also control the start and stop of the discharging process, again based on the lithium battery's status. This is crucial for preventing over-discharge and ensuring the battery operates within safe limits.
Automatic Lithium Battery Activation: For compatible inverter models (3KW/4KW/5KW/10KW/15KW), an "Active Function" is available. If the battery wiring and commissioning are successful, and the battery is not detected, this function, when enabled in the bundled software, allows the inverter to automatically activate the lithium battery upon being powered on. This simplifies the commissioning process.

Important Technical Specifications:

While specific electrical ratings for the card itself are not explicitly detailed, the manual highlights several important technical aspects:

Compatibility: The device is compatible with a range of inverters, including:
- Hybrid inverters: 3KW, 4KW, 5KW, and 5.5KW
- 3-phase hybrid inverters: 10KW and 15KW
- Single phase off-grid inverters: 4KW/5KW
- Split phase off-grid inverters: 6KW
- Online 48V 3KVA/5KVA/6KVA UPS
Communication Protocol: The device utilizes the RS-485 communication protocol.
RS-485 Box Power Supply: The RS-485 external box requires a 12V DC/1A power source. Users need to purchase an AC/DC adapter separately for this purpose. The adapter plug dimension is specified as OD=5.5mm and ID=2.5mm.
Storage Temperature Range: The admissible storage temperature range for the card/box is from -10°C to +70°C. Storage must be in a dry place.
Baud Rate: The recommended baud rate for communication with BMS is 9600bps.
Parity Check: The recommended setting for communication with BMS is "no parity check 1 stop bit."
Maximum Lithium Battery Groups: The system supports a maximum of two groups of lithium batteries. The maximum number of batteries per group should be confirmed with the battery manufacturer.

Usage Features:

The BMS RS-485 Card/Box offers several user-configurable features to adapt to different system setups:

Communication Format Configuration (SW2 Dip Switches):
- Baud Rate: Configurable to 2400bps, 4800bps, 9600bps (default), or 19200bps using Bit #1 and #2.
- Parity Check: Configurable to Even parity, Odd parity, No parity check 1 stop bit (default), or No parity check 2 stop bits using Bit #3 and #4.
- Recommended Setting for BMS: 9600bps baud rate and no parity check 1 stop bit (Bit #1 OFF, #2 ON, #3 ON, #4 OFF).
RS485 Resistance Configuration (SW2 Dip Switches):
- Push Up Resistance: Configurable to Enable (default) or Disable using Bit #6.
- Push Down Resistance: Configurable to Enable (default) or Disable using Bit #7.
- Terminate Resistance: Configurable to Enable (default) or Disable using Bit #8.
- The switches are configured by pushing them down for "OFF" and up for "ON."
SW1 Reset: All dip switches in SW1 should be set to "OFF" status (Disable) by default for all bits (#1 to #8).
Lithium Battery Communication Configuration (ADD Switches on Lithium Battery):
- Baud Rate: Dip 1 on the lithium battery's ADD switch represents the baud rate. "ON" (upper position) signifies 9600bps.
- Battery Group Address: Dip switches 2, 3, and 4 on the master battery are used to set up or change the group address. "1" is the upper position, and "0" is the bottom position.
  - Single group only: Dip 2=0, Dip 3=0, Dip 4=0 (master battery setting).
  - Two-group condition (first group): Dip 2=0, Dip 3=0, Dip 4=0 (master battery setting).
  - Two-group condition (second group): Dip 2=1, Dip 3=0, Dip 4=0 (master battery setting).
  - A restart is required for these settings to take effect.
Interface Configuration: Detailed pin configurations for the RS-485 ports on both the card/box and the lithium battery are provided, including RS-485 - B, RS-485 - A, and GND connections.
Visual Feedback on LCD Screen: After successful installation and communication, the inverter's LCD screen will display specific icons to indicate successful communication with the lithium battery:
- For Hybrid inverters (3KW/4KW/5KW/5.5KW, 3KW/4KW/5KW/10KW/15KW) and Split phase off-grid inverter 6KW: The frame of the battery icon will flash, and a "Li-bAt" icon will light on.
- For Single phase off-grid inverter and Online UPS: A "Li" icon will light on.
Error Codes (for 3KW/4KW/5KW/10KW/15KW models): The LCD screen will display specific codes to inform the user about the battery's status:
- "60": Informs inverter to stop discharging battery.
- "61": Informs inverter to stop charging battery.
- "62": Informs inverter to charge battery.

Maintenance Features:

The manual emphasizes the importance of proper storage conditions if the device is not immediately installed:

Dry Storage: The card/box must be stored in a dry place to prevent damage.
Temperature Control: Storage within the admissible temperature range of -10°C to +70°C is crucial for preserving the device's integrity.

In summary, the BMS RS-485 Card/Box is an essential component for integrating lithium batteries with compatible inverters, providing intelligent communication for optimized performance, protection, and simplified operation of the entire power system.