I installed a power monitor, but the measured values seem to differ from the actual values.

For power monitors, you need to set up CT and VT ratios. (In the case of the PR300 power monitor, phase, wiring method, voltage range, and other settings are required in advance.) However, even when you enter these settings, there are times when the measured values differ significantly from the actual values. In such cases, check the active power (W). It can be negative, or smaller than actual. (When the active power display is negative, this indicates that power is being supplied (regenerated energy) to the power supply from the load.) In this case, recheck the current/voltage input wiring, and the orientation and phase of the attachment of the CT.