Firmware Update | Easun
Check the sticker on the side or the LCD info screen:
Example: U1 = 12.21, U2 = 12.11
Do not mix firmware between different hardware revisions (e.g., 5.6kW vs 3.2kW, 48V vs 24V).
Yes—if you are methodical, technical, and patient. For the average homeowner who just wants lights to turn on during a blackout, do not touch the firmware. For the solar enthusiast squeezing every drop of efficiency from a budget system, the Easun firmware update is the key to unlocking stalled potential.
Remember the golden rules:
If you follow this guide, you will turn your off-the-shelf Easun inverter into a reliable, high-performance power station. If you skip the steps, you will own an expensive paperweight. The choice, and the soldering iron, is yours.
FAQ: Easun Firmware Update
Q: How often does Easun release firmware updates? A: Rarely. Maybe once every 18 months. Most updates are community-driven reverse engineering.
Q: Can I update via Bluetooth? A: No. The Bluetooth dongle is for monitoring only. It cannot send a bootloader payload.
Q: My neighbor bricked his unit. Can a repair shop fix it? A: Yes, if the shop has a JTAG programmer and can source the original EEPROM dump. Cost usually exceeds the value of the inverter ($100-$200). Buy a new control board instead.
Q: Does the update reset my BMS communications? A: Yes. You must re-pair the inverter with your battery BMS (reset DIP switches or redo Pylontech handshake).
Final Verdict: Proceed with caution, but proceed. A successful flash transforms your Easun from a budget compromise into a competitive powerhouse. easun firmware update
This guide outlines the standard procedure for updating the firmware on EASUN POWER solar inverters. Firmware updates can resolve software bugs, improve battery compatibility (especially for LiFePO4), and optimize charging logic. ⚠️ Critical Pre-checks Identify Your Model
: Firmware is specific to the hardware version (e.g., SMG II, ISolar SMX, IGrid). Installing the wrong firmware can permanently brick your inverter. Check Current Version
: Navigate to the LCD menu (usually the last few screens) to note your current U1 (Main CPU) and U2 (Secondary CPU) versions. Stable Power
: Ensure the inverter is connected to a stable battery bank or utility power.
update using only solar (PV) power, as a passing cloud could cut power and fail the update. Phase 1: Preparation Request Firmware
: Contact EASUN support or your official seller with a photo of your inverter's side sticker (showing the serial number and model) to receive the correct Hardware Needed A Windows laptop.
The manufacturer-provided RS232-to-USB cable (or a specialized RJ45-to-USB cable depending on the port). Software Tools : You will typically need the ReflashTool InverterCheck utility provided by EASUN. Phase 2: Connection Connect the laptop to the inverter's Communication Port (RS232/USB). Device Manager
on your PC to identify the assigned COM Port number (e.g., COM3). Turn the inverter's power switch to
(the screen may stay on if batteries are connected, but the inverter should not be actively "working"). Phase 3: The Update Process Run the Tool : Open the update software (e.g., ReflashTool.exe : Select the correct
and set the Baud rate (usually 9600 or 19200, as specified in the update instructions).
: Click "Open" or "Browse" and select the firmware file provided by support. The inverter LCD will typically show "UP" or flash symbols. Do not disconnect the cable or power off the PC until the software shows "Update Successful." Check the sticker on the side or the LCD info screen :
: Once finished, disconnect the cable, turn the inverter switch to OFF for 30 seconds, then back to ON to initialize the new software. Troubleshooting Communication Failed
: Check that your USB-to-Serial drivers (usually CH340 or Prolific) are installed correctly in Windows. Wrong File Error
: If the tool rejects the file, do not force it. Verify the model version with the seller again. Stuck at 0%
: Try a different USB port or a shorter cable. Ensure no other monitoring software (like SolarPower or WatchPower) is running in the background. Do you have a specific EASUN model number particular issue you're trying to fix with this update?
Updating the firmware on an EASUN inverter is a critical process often used to fix parallel synchronization issues (Error 42), MPPT performance, or fan control bugs
. Because EASUN inverters are often clones of Voltronic Axpert designs, using the wrong firmware version can brick the device. Power Forum Pre-Update Checklist Identify Version
: Check your current version on the inverter LCD or through the manual to ensure compatibility. Power Source
: Disconnect all PV (solar) input and loads. The inverter should be powered only by the battery Hardware Connection
: Connect your PC to the inverter's USB or RS232 port. If using a Wi-Fi datalogger, disconnect it first. Clean State : It is highly recommended to perform a factory reset
(press UP and DOWN buttons simultaneously for several seconds) before starting. DIY Solar Power Forum Firmware Update Procedure Download the Package : Obtain the specific firmware and flash tool (e.g., ReflashToolX ArenaFlash ) from the official EASUN Help Center or reliable community sources like Power Forum Set the Switch : Press the inverter's power switch to the position. The LCD may remain lit for about 30 seconds. Execute the Flash Open the flash tool on your PC. Select the correct firmware file ( Timing is Key
: Start the update tool immediately after powering up the inverter. Some users find success only when starting the transfer within seconds of a cold boot. Completion : Wait for the tool to show "Update Success." Do Example: U1 = 12
interrupt the power or disconnect the cable during this time, as it will damage the device's bootloader. Power Forum Troubleshooting & Tips Easun SMW 11KW #72 - syssi/esphome-smg-ii - GitHub
What is Easun Firmware Update?
Easun is a brand that specializes in solar charge controllers, inverters, and other renewable energy products. A firmware update is a software update that is used to improve or modify the functionality of these devices.
Why is a Firmware Update Needed?
Firmware updates are released to fix bugs, add new features, or improve the performance of Easun devices. These updates can:
How to Update Easun Firmware
The process of updating Easun firmware may vary depending on the specific device and the type of update. Here are general steps:
Precautions
Before updating the firmware:
If you're looking for specific information on updating your Easun device, please provide more details about your device and the update you're trying to perform. I'll do my best to guide you through the process.