How to black start HS2.5/HS3.6 battery system?

The equipment can provide Black Start capacity, meaning that our energy
storage inverter and battery can continue to run even if the power grid and
photovoltaic panel are out of service. The startup procedure for Black Start is as
follows:
In case of pressing and holding the POWER button for less than 20 seconds,
the status light will flash green light for 1 second and then turn off for 4 seconds, with a period of 5 seconds.
After pressing and holding the POWER button for more than 20 seconds (including 20 seconds), the status light will come on solid green light, and SOC
power indicators will flash as follows:
• Firstly, the indicator SOC3 comes on green, and the rest of indicators are off;
• Secondly, the indicators SOC2 and SOC4 come on green, and the rest of indicators are off;
• Thirdly, the indicator SOC1 comes on green, and the rest of indicators are off;
• Finally, all power indicators are off.
The POWER button should be released at anytime in the process.