The B21-311 energy meter is a 65A direct connect device designed for single-phase power systems operating at 230 VAC. It features two output ports and two input/IR ports. The meter offers high accuracy, with a class 1% rating for active energy and a class 2% rating for reactive energy. It has a measurement range of 220-240 V between the neutral and line connections. With an IP20 protection degree, this energy meter provides reliable performance in various environments. It also includes a backlit pixel-oriented LCD display, ensuring clear visibility of the readings. As part of the Silver functionality sub-group, this meter offers several features such as measuring active, reactive, and apparent energy. It supports import/export of energy and has resettable energy registers. Users can choose between Class 0.5 or Class 1 accuracy levels based on their requirements. Additionally, the meter supports tariffs and fixed I/O configurations. It provides pulse output/alarm functionality to enable external monitoring or triggering based on specific conditions. The B21-311 energy meter is designed to be mounted on a DIN rail and occupies two modules of space.