1. Select multimeter range.

The multimeter has a DC voltage of V in five ranges of 2.5 V, 10 V, 50 V, 250 V, and 500 V. Select the range according to the input voltage of the breakout board. If do not know the input voltage of the board or the output voltage of the server power supply, use the highest voltage to measure the input voltage of breakout board and gradually change to a low voltage range.

2. Method of measurement.

The multimeter shall be connected in parallel with the input circuit of the breakout board under test and the input port of the switching power supply of the breakout board. Red Pen should be connected to the input power positive terminal port of breakout board, black pen should be the input power negative terminal of the breakout board.

3. Correct reading.

Watch the dial carefully, keeping your eyes on the pointer. In this way, the mining power server voltage measurement is completed, the server output voltage equals to the input voltage of the breakout board.

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