Figure: Taking RJ8921P electrical parameter power measuring instrument as an example, RJ is short for the company, 89 represents the power meter series model of Ruijie, 2 represents the precision of the power meter, 1 represents the single channel, so RJ8921P is a single channel power meter with 0.2 precision

Similarly RJ310 power analyzer is a single channel 0.1 level precision high precision measuring instrument.

In this way, customers need to know how many channels (such as the product under test is three-phase will be used at least 3 channels) and precision requirements of 0.1 level; 0.2 grade; 0.5 grade can be quickly selected.