The difference and connection between Whatsminer M20 series and M30 series hash board maintenance are as follows:
1. When testing the hash board, the power supply voltage of the M20 series hash board is fixed at 13V, and the power supply voltage of the M30 series hash board needs to be set to different test voltages, which are determined by calculation according to the number of ASIC chip layers and the voltage between layers.
2. The CLK signal voltage of the M30 series needs to be detected by an oscilloscope, and whether it is normal by observing the waveform. Because the CLK signal voltage is on some hash boards, 0.15V can also work normally, leading to misjudgment.
3. To repair the M20 series hash board, you need to pay attention to the voltage between layers, which is generally higher than 0.3V. Repair the M30 series hash board, do not need to pay attention to the voltage between layers, sometimes lower than 0.3V, the hash board can also run normally.
4. Use an oscilloscope to test the CLK signal waveform. Power on the hash board to test it. When testing the RXD, TXD and RST signal waveforms, you need to enter the test command "test-readchipid" to measure the waveform.