Single-phase and three-phase IPDU intelligent meters are based on innovative SUM (sustainable, scalable and maintainable) design concept technology. As a key component of metered cabinet distribution unit (PDU), they can provide active metering function after loading into the main body of the PDU, so as to realize energy optimization and circuit protection. User-set alarm thresholds can effectively reduce risks by sending real-time local and remote alarms to warn of potential circuit overload. Metered rack-mounted PDUs provide power usage data to enable data center managers to make informed decisions about load balancing and appropriate IT sizing, significantly reducing total cost of ownership. Users can access the metered cabinet PDU over Ethernet or RS485. This series of products can be widely used in IDC, banks, securities, government, enterprises and other data center room.