Whatsminer P21 power supply is sui for M20, M21, M21D, M20S and M21S. Its interior is composed of a base board and a main board, mainly including EMI filter circuit, PFC circuit, auxiliary power area and main power area. 220V AC passes through these main circuits, after filtering and rectification, finally outputs 12V DC voltage. This video mainly explains the maintenance knowledge from the basic structure and powering process of the P21 PSU.
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